I am a 6th Grade Earth Science and Math teacher at Hockinson Middle School in Brush Prairie, Washington. I am the Mathematics, Engineering, Science Achievement (MESA) advisor and I am a NASA Endeavor Fellow. Each of these experiences gives me the opportunity to interact with curious young people, experienced teachers, and parents,community members, and administrators who care about the future of STEM opportunities. I have a master’s degree in teaching, a K-8 teacher certification and, upon completion of the NASA Endeavor Science Teaching Project, will have a STEM teaching certificate from Columbia University’s Teaching College. Thereafter, I plan to complete the professional certification process in my state. As a NASA Endeavor Fellow, I have been given a unique, rare opportunity to complete a two-week internship at NASA Goddard with my mentor scientist, Dr. Charles Gatebe. The goal of this internship is to learn by watching, interacting, and doing work with members of the NASA team. In turn, I am planning science curriculum that integrates NASA materials into the classroom. If I were to describe myself in a couple of words, it would be that I love to learn!

Kim Abegglen in front of a spherical integrating sphere during the calibration of NASA Cloud Absorption Radiometer at NASA GSFC. (Photo by CK Gatebe).

Doing science is EXCITING! I can hear some of my sixth graders now, sighing, rolling their eyes, and saying under their breath, “Really now, Ms. Abegglen? Really?” I say to the skeptical, yes, indeed. Doing science is exciting. Today I spent my first day at NASA Goddard Space Flight Center in Greenbelt, Maryland working with Dr. Charles Gatebe and two teacher-researchers, Robyn and Jim. After picking up my very cool NASA badge, I was greeted by my host, Dr. Charles Gatebe. Without a minute to waste, my two week science experience/adventure/internship began as we walked into Dr. Gatebe’s building. Dr. Gatebe EXPLAINED to me the purpose of satellites like TERRA and AQUA that collect data about Earth systems. I INTERACTED with scientists and their high school, undergraduate and graduate student interns. I EXAMINED data instruments including a Cloud Absorption Radiometer (CAR) and sun photometers. I ASKED colleagues QUESTIONS as they shared their projects. They COMMUNICATED their investigations, results, frustrations, and ideas for further consideration. We COLLABORATED as we shared possible problem-solving strategies. I READ and STUDIED about climate and evidence of climate change using interactive technology. I spent the day with an EXPERT. Every interaction I had today with NASA Goddard science-doers had an undercurrent of EXCITEMENT. They were excited by their questions and projects. They were excited to share their ideas, their knowledge and their experimental results. They were excited to be doing science!

Some may ask why all the capitalized words like EXPLAINED, EXAMINED, ASKED, etc. My students know that I capitalize when I share something that I think is important. Today I EXPERIENCED the doing of science–I could smell it, see it, hear it, and touch it. Doing science is EXPLAINING, ASKING, COMMUNICATING, COLLABORATING, READING, STUDYING, EXAMINING, INTERACTING, ENGAGING EXPERTS and being EXCITED by your wonderings, ideas and questions. My project here is help teachers and students “do science” rather than “learn science”. So, you ask, what will I DO for the next two weeks at NASA Goddard? Science, of course!

I Did Science, So Can You! A Fine Farewell!

My two weeks at NASA Goddard has flown by and has been filled with so many interesting experiences. So as I sit at my computer in my NASA office for what will be my last hour of this adventure into the world of Goddard, I’d like to share some of what I’ve learned before I fly back to my own world of family, friends, and school in Brush Prairie, Washington.

First, I am a student as much as I am a teacher. I leave here with new understandings of a broad spectrum of ideas. I spent time in the Radiometric Calibration Facility, learning from Dr. Gatebe, Rajesh Poudyal, and John Cooper how the Cloud Absorption Radiometer (CAR) is calibrated. While I was there, I learned that collecting and analyzing data can be time-consuming and not glamorous. But I also learned that when you are motivated by a question you really want to know the answer to, you persevere through the frustration and/or boredom and focus on the big picture: accomplishing your goal, whatever it may be. There is joy in success!

Second, I can take every learning experience to help me to become a more experienced, compassionate family and community member. In addition to the science, I have gained something from everyone I have interacted with here at Goddard. That is true of everyone I meet, but I think this adventure was something different and unique. Away from my family and the responsibilities that come with them, my focus during these two weeks has been on what is happening now, with no distractions. Out of my comfort zone, I initiated conversations with others and prompted discussions of their jobs and interests. One can learn much from others if we only take the time to ask and then listen.

Third, what I think I can do and what I can actually accomplish are not always the same. Be open to unknown opportunities and challenges–you may achieve something that you never thought possible because you were unaware that you had the ideal qualities, attitude and skills. When I applied for this internship, I really had no idea that I would be selected. It was such an exciting surprise! But then I wondered if I could do it; would I understand what was being shared with me and would I find confidence to ask questions when I didn’t understand. I was a little afraid! But I did it, I’m doing it and I accomplished what I set out to do. If I hadn’t applied, a potential learning experience would have lost to me. Take every opportunity afforded you–you can do it, too!

My two weeks at NASA Goddard is really the beginning of my NASA internship. From my experiences working with NASA team members, I am now in the process of developing curriculum for grades 5-8. I will continue to collaborate with Dr. Gatebe as I finish developing and field testing a three-week unit entitled, “Self-Assessing Scientific Practices in an Integrated Science Context: The Sun is the Primary Source of Energy in Earth’s Climate System.” In this unit, students will explore light, radiation, the Earth’s Energy Budget, albedo and climate while self-identifying scientific practices. The main learning objective is to explore the Sun’s critical role in global climate while practicing thoughtful scientific skills.

During my internship I came to know about the upcoming GLOBE Student Climate Research Campaign (2011-2013) that will increase climate change understanding among students, and how a number of NASA scientists, including my host, have been helping in the planning process. My work is relevant to this program, and upon my return to my home institution, I plan to find out more about opportunities for participation. Also, I think it would be a good thing for science teachers (including GLOBE teachers) to seek similar internship opportunities with large science organizations such as NASA, to update their scientific research experience from time to time.

As a final thought, I leave NASA Goddard awed by our Earth. While I have never seen it from space, though it was described to me by the Atlantis STS-132 crew during their visit to Goddard on 29 July, 2010, I have spent time looking at it through the eyes of scientists who study pieces of it in the attempt to understand it better as a whole. Our home, Earth, is an amazing, incredible place. There is a beautiful, mysterious dance occurring as we speak between all of Earth’s systems. We are all a part of these complex, interconnected systems. So, in closing, I would ask you to consider these questions: what is your unique part in Earth’s systems, what is your unique impact, and what is your responsibility to the systems that afford you your life?

This summer, NASA launched a new initiative in support of the president’s Educate to Innovate campaign for excellence in science, technology, engineering and mathematics (STEM) education, where thousands of school teachers and students will engage in stimulating math and science-based education programs at NASA centers. We accepted three teacher interns for summer placement in our Lab at NASA Goddard: one from the Endeavor program and the other two from the Science Teachers and Researchers (STAR).

L-R: James Ruff & Robyn Williams in front of a spherical integrating sphere, which is used for calibrating radiometers at NASA GSFC. James and Robyn participated in the calibration of NASA Cloud Absorption Radiometer, which flies on NASA P-3B (http://car.gsfc.nasa.gov). (Picture by CK Gatebe

We are excited to introduce the 2010 STAR Fellows (James Ruff and Robyn Williams), who have already begun their internship (June-August) at our lab. James aspires to be a physics educator for high school students, while Robyn aspires to be a biology educator for high school students.

The Endeavor Fellow (Kim Abegglen) will report in mid-July for a period of two weeks, but will continue working with us remotely during the school year.

Towards the end of their summer research, the fellows will share with you their excitement, experiences and lessons learned from the frontlines and trenches of science. All the interns are interested in participating in the upcoming GLOBE Student Research Campaign on Climate (2011-2013).

James Ruff

I am a teacher from Baltimore, Maryland. I received my Bachelor of Science in physics from Loyola College in Maryland. Following graduation, I worked for a couple of years at Westinghouse Electric Corporation in reliability engineering on a radar jamming pod placed under the F-16 fighter jet. As the Berlin Wall fell, so did the defense budget and I went off on my own an opened a small deli in Richmond, VA. I ran the business for ten years then decided to follow my heart and start teaching physics. I started during the 2005-6 academic year with Baltimore City in physics and found myself slowly being moved to teach ninth grade Earth Science and technology classes. While in Baltimore City, I participated in the Integrating Teacher Quality – Through Opportunities in Physics and Physical Science program at Frostburg State University, the Smithsonian Science Educator Academy in Washington, D.C., and the TI NSpire workshop in Edmonton, Alberta. In 2009, I left the Baltimore City School System to finish the Master of the Arts in Teaching program full time at Towson University. Here I received the coveted Robert Noyce Scholarship for STEM teachers and additionally was accepted as a Science Teacher and Researcher intern at NASA Goddard Space Flight Center. I graduated May 2010 specializing in secondary science education and am a member of Kappa Delta Pi, the international honor society in education. At the NASA Goddard Space Flight Center, I am proud to work with Dr. Charles Gatebe in the Climate and Radiation Branch and learn about the GLOBE program.

L-R: James Ruff & Robyn Williams observing a light spectrum through a monochromator at different wavelengths. The experiment was conducted in a calibration laboratory at NASA GSFC. James and Robyn observed different rainbow colors and used an instrument to observe the invisible light – ultraviolet and infrared colors. (Picture by CK Gatebe).

Robyn Williams

I am a Science Teachers and Researchers (STAR) Intern at the NASA Goddard Space Flight Center in Maryland. During this internship, I will be working with scientists to create an activity for the GLOBE program.

I began my higher level schooling at the University of Maryland, Baltimore County (UMBC) where I decided to major in Biological Sciences. Towards the end of my sophomore year, I decided to apply for a new scholarship that was going to be offered at UMBC, the Robert Noyce Scholarship. This scholarship is for students who hope to become future science teachers. Through this scholarship program, I was given the opportunity to take free education classes where I would be able to teach science to high school students before officially accepting the award.

During that summer, I taught physics and biology to the students in the Upward Bound program. During the first part of the summer, I was given the opportunity to use various physics simulations and molecular programs to teach heat transfer. The students were also engaged in an experiment that would require them to keep a hot dog hot and a juice box cold while both were in the same container. The students learned about what materials would be better insulators and what materials would be better conductors.

After the physics unit, we, teachers, were paired with an Alice Ferguson Foundation program, “Bridging the Watershed”, to teach students about chemistry and biology and for them to complete experiments outside in the field. During this program, we had to design 5 lesson plans, based on the 5E model, which would be taught to the students, one of which would have the students taking a field trip to a state park to do their experiment. Because I was teaching about invasive plant species, I had to teach the students how to properly identify the plants and how to pick a section in the park to study. After the summer of my sophomore year, I decided to accept the scholarship award and begin my journey to become a biology teacher.

As a STAR intern at NASA, I hope to learn about the different educational resources that they offer to students and teachers. I hope to observe how scientists are able to communicate their findings among themselves and the public. I also look forward to gain first hand research experience and to help bridge the gap between teachers and scientists. At the end of this program I hope to have created an activity that would link the GLOBE protocols to global climate awareness in order to increase climate change understanding among students.

The recent oil slick in the Gulf of Mexico is an example of a large environmental event that can have multiple ramifications. The oil slick resulted from an explosion that occurred on April 20, 2010, on the Deepwater Horizon rig, causing it to sink to the ocean floor and breaking a pipe, from which millions of gallons of oil have leaked.

This true color satellite image obtained from the NASA Earth Observatory website was acquired on April 29, 2010 by the Moderate-resolution Imaging Spectro-radiometer (MODIS) sensor aboard the NASA Terra satellite flying around the earth at a 705 km high orbit. The greenish and brownish land surfaces in the upper half of the image are contrasted with the darker ocean waters in the lower half. The whitish features of different shapes and sizes that look like paint over the land and ocean surfaces are clouds. The oil slick is shown enclosed in a rectangular white box near the center of this image. The scale at the lower right part of the image allows us to visualize how extensive the oil slick was on April 29; well over 100 km in diameter.

In fact, calculations of the approximate amount, area coverage, and thickness of the slick have been provided at the NASA Space Math website, click on Problem 339), which shows many excellent examples of useful mathematical applications in earth and space sciences for students. About 10 days after the incident, it was estimated that about 2 million gallons of oil had already leaked, and covered an area of over 6,000 km2 of the ocean surface.

Since the oil spill occurred, different emergency response teams and other agencies have made intensive efforts to try to contain the oil leak as it has spread across both the surface and floor of the ocean. Such efforts are geared toward stopping the leak and limiting the spread of the oil. As we can imagine, if such measures are not taken urgently, the oil could have many unpleasant consequences for the affected ocean and land ecosystems (the physical and biological components of these environments) including the plants and animals that inhabit them, and the humans who depend on ocean and coastal ecosystems for food and water.

How do satellite sensors acquire information from space?

One may wonder, how it is possible for a satellite sensor to see the oil slick from as far away as 705 km above the earth’s surface, even though it may not be easy to see it with the human eyes from a few kilometers away. You may also wonder why the oil slick appears light colored on this image even though oil slicks are typically very dark in color. This demonstrates the power of ‘remote sensing’, which is the science of making measurements from far away, without physical contact with the object being measured. Satellite remote sensing is one of the most powerful and efficient ways of monitoring Earth in modern times and documenting different events. This is achieved by making instruments or sensors that measure the intensities of different types of electromagnetic radiation, which includes visible light, as well as other types of radiation that are invisible to the human eye, such as X-rays, ultraviolet (UV), and infrared (IR). These different electromagnetic waves travel with different wavelengths (which is the distance between the midlines of two consecutive crests or troughs of the wave). Detailed discussion of the electromagnetic radiation is beyond the scope of this blog. However, although the radiation measured in remote sensing can be from different sources, in the case of the above image, it is the reflection of sunlight from the various features and objects on the earth and ocean surfaces, as well as the molecules and particles in the atmosphere, such as air, aerosols (described in my previous blog), and clouds. The intensities of sunlight reflected at different wavelengths are measured by the satellite sensors, and transmitted to ground receiving stations, where they are recorded and forwarded to processing centers. By combining the measurements at different wavelengths on the computer according to logical scientific principles, a variety of images of the scene can be created. Depending on how the data are processed, different objects on the scene can be made to appear more prominently than some others. This is made possible because the surfaces and objects in the scene reflect and/or absorb the Sun’s radiation differently at different wavelengths. A more detailed discussion of how remote sensing works will be presented in a future blog.

Even with the capability to display satellite data as images, in such a way that certain objects and surfaces could appear more prominently, absolute confirmation of what an object really is can be achieved by matching the characteristics of these objects on the image with related observations made at close range on the ground. Such close range observations that are known with absolute certainty are referred to as “ground truth”. Whereas ground truth can only be obtained over limited areas, when combined with satellite observations, very large areas can be monitored considerably well. For instance, in the case of the satellite image shown above, it has been possible to visualize, practically in an instant, an area of ocean surface over 6,000 km2 covered by the oil slick, by linking the testimony of human observers, who have seen the oil in a small area on the ocean surface, to the satellite image. Without the knowledge from the ground that this is surely an oil slick, just by seeing it on the satellite image alone, it might have been mistaken for something else, such as ocean sediments or even clouds. On the other hand, without this satellite observation capability, such a large area over the ocean could have taken months to measure, even by the most advanced ship-based mapping technique. Now that the oil slick has been recognized and detected, it can be mapped accurately and its spread monitored from several satellites that pass over the area daily, until the slick breaks up so much so that it is no longer visible from satellite. For example, the image below was acquired on May 4, 2010 (one week after the previous image) by another MODIS sensor aboard a different NASA satellite called Aqua, and obtained from the MODIS Rapid Response website. This time, the image is displayed on an online mapping system called GoogleEarth, so that the oil slick’s location could be seen relative to accurate map features, such as the land/sea boundaries in yellow, and the position of the city of New Orleans. The oil slick is shown enclosed in a white box. I leave you to compare the position, shape, and size of the oil slick on the two images in this blog acquired one week apart. Bearing in mind that the oil is gradually breaking up and spreading: What are your observations or conclusions?

An important lesson to learn from this blog is that many environmental events and situations that can affect our lives and even our climate can be monitored from satellite, but observations and measurements on the ground are equally important for accurate identification of such events and situations. Students everywhere can help in acquiring the ground-truth information that can contribute toward solving important problems related to our environment and climate by active participation in various programs coordinated by GLOBE, which has very close relationships with agencies responsible for environmental and climate monitoring from satellites.

The recent volcanic eruption in Iceland marked by the spectacular “curtain-of-fire” and near-complete shut-down of air travel in Europe in mid-April will probably earn a place in the history books (see pictures of the Icelandic volcano at the Washington Post.)

The Icelandic Volcano. Credit: Washington Post

Two of the most commonly cited volcanic eruptions in the climate literature are Krakatua (1883; Indonesia) and Mt. Pinatubo (1991; Philippines). The most massive explosions of Krakatua took place in August, 1883, and rank among the most violent volcanic events in recorded history. In the year following the eruption, average global temperatures reportedly fell by as much as 1.2 °C (2.2 °F). Weather patterns continued to be chaotic for years, and temperatures did not return to normal until 1888. The eruption injected an unusually large amount of sulfur dioxide gas high into the stratosphere, which was subsequently transported by high-level winds all over the planet. This led to a global increase in sulfurous acid concentration in high-level cirrus clouds and the clouds became brighter. The increase in cloud reflectivity (or albedo) meant that more incoming light from the sun than usual was reflected back to space, and as a result, the entire planet became cooler, until the suspended sulfur fell to the ground as acid precipitation.

In June 1991, the best-documented explosive volcanic event to date and the second largest volcanic eruption of the twentieth century took place on the island of Luzon in the Philippines, a mere 90 kilometers northwest of the capital city Manila. Up to 800 people were killed and 100,000 became homeless following the Mount Pinatubo eruption, which climaxed with nine hours of eruption on June 15, 1991. On June 15, millions of tons of sulfur dioxide were discharged into the atmosphere, resulting in a decrease in the temperature worldwide over the next few years.

Pinatubo eruption provided scientists with a basis for constructing or modeling the change in Earth’s radiation balance (scientists like to call this change “radiative forcing”) due to explosive volcanoes. It is now well established that volcanic eruptions cause the stratosphere to warm and the annual mean surface and tropospheric temperature decreases during a period of two to three years following a major volcanic eruption. If you are interested in more technical details on how volcanoes affect climate, you can read a very good paper written by Alan Robock. Given that the Icelandic eruption is along a Mid-Ocean ridge and volcanic Hot spot, do you think the gases and aerosols will be of different composition than the Krakatoa and Pinatubo eruptions, which are associated with plate subduction along convergent plate boundaries? If there is a difference, what effect might that have on weather and climate over the next few years?

So the disruption of the air travel by the Iceland’s Eyjafjallajökull Volcanic eruptions is just the beginning; other weather and climatic effects will follow.  In the days and months ahead, we are likely to experience darkened sky and spectacular sunsets in different parts of the world.

A few weeks ago I spent an evening visiting relatives (they shall remain unidentified to protect the guilty).  When I arrived at the house, there were several lights on.  I rang the doorbell.  I knocked.  The dog barked, but no one answered.  The door was not locked, so I went into the house and said hello to the dog.  The house has a main floor, an upper floor, and a basement.  There were lights on at all three levels.  I called out – no one answered on the main level.  I went to the stairs and called up – no one answered.  I went to the basement stairs and called down – still no answer, but now I could hear voices.  I walked downstairs and found the television on, but still no people.  Hmmmm….

I headed back to the main level.  At that point, the parents of the family came home and I learned that their boys had been home most recently, and had left all these lights and things on.   Hmmm….

There has been much discussion about how sure we are about the prospects for climate change and resulting bad effects, and whether therefore we need to begin to take action now.  While we do not yet know the exact timing, size, and details of these bad impacts, this experience with the “house of lights” made me wonder:  How sure would someone have to be about climate change impacts to take such simple actions as turning off the light or the television when they are not even in the room (or the house!)?

An interesting – and entertaining – discussion on the related question of risk assessment can be found on YouTube.

Teddy Roosevelt, US President from 1901-1909 said:  “[Future generations] will reproach us, not for what we have used, but for what we have wasted…”

In this case, it was the other way around:  I found myself reproaching the younger generation for the waste in the “house of lights”.  Because really, one of the best and easiest ways to address the risks of climate change is to stop wasting energy and it is also a win-win-win-win scenario:
Win 1:  It reduces power bills (saves money)
Win 2:  It reduces the demand for energy and thus the need to construct more power plants
Win 3:  It reduces the pollution created as a by product of electricity generation
Win 4:  It reduces the emission of greenhouse gases that trap additional heat in our atmosphere.

Some might make the argument that turning lights off has other negative consequences, but the TV show Myth Busters demonstrated very scientifically that this is not the case.

Others might argue that one person turning out a light can’t possibly make a difference, but here is a nice activity that presents some back of the envelope calculations on how the impact can be multiplied if every “one” person takes that same action. It adds up!

So how about it?  Are you sure enough about the possible risks to turn off lights you aren’t using?  Given the win-win-win-win of the situation, I know I am!

“Daddy, how long is a billion years?”

As soon as we got in the car this morning, and buckled up, I said “so Jordi, I need some help. I need more material for the blog.” “Daddy, what do you mean by ‘material’?”  “That’s what writers call the stuff they use to create stories”, said daddy.

Earth from MESSENGER spacecraft as it flew by Earth on August 2, 2005. MESSENGER goes into orbit around Mercury on March 18, 2011.

It was a beautiful, sunny morning, so he started talking about … the Sun. He had lots of questions—where did it come from, what’s burning on it to make it so bright, how old is it, what will happen to Earth when it stops burning? The last one was particularly cool. I asked him if he thought the question “what will happen to the Earth when the Sun dies?” is something lots of kids might ask. He said “yes!!” I asked him who he thought was the first person to actually figure it out. He didn’t know. I told him it was me.

When I was a grad student at Penn, one of the undergrads in the class I was teaching asked that question. I didn’t know the answer, so I told her I’d find out. I tried but I couldn’t. Nobody had done it before. So I decided to be the first. I didn’t know if I could, and I didn’t know what I’d find, but it was incredibly exciting—and that’s science. Here’s the result. (And it was far from the end of the story.)

Jordi said, “YOU DID?” I looked at his surprised face in the rearview mirror and said “yup, your daddy.” Then he said, “that’s sooo strange! That’s sooo cool! I asked a question that YOU figured out!!” He was very proud. I felt so connected to him. (We’ll see later if he told his friends.) And I promise that I’ll make this story into a blog post, because now YOU’RE waiting for the rest of the story.

By the time we arrived at the school 20 minutes later, I had a month’s worth of ‘material’ for Driving with Jordi (stay tuned). The conversation was incredible. At one point though, Jordi ran into a conceptual wall when I was talking about the Sun’s lifetime being 10 billion years, and that it’s now half way through its life. He said “Daddy, how long is a billion years?”—which is why I wrote this post.

It is actually such an important question, and I thought about it all the way home. It’s at the heart of a key recurring problem in science education in that the VAST majority of humans truly don’t understand lengths of time that are far longer than our lifetimes. No wonder that folks don’t understand global warming as due to human intervention, and think it reasonable to interpret the data as explained by natural variation in the environment over long timescales. No wonder that folks don’t understand the timescales for evolution of species.

So here now is a novel way to look at it. Thanks Jordi! I think this will help lots of folks understand something they’ve never understood before.

Humans and Time

We humans now live on average about 75 years (in the developed world; in Africa the life expectancy is frighteningly low at 32 to 55). I’ll assume that 75 years is the life expectancy of a human in the absence of devastating diseases like AIDS, and with availability to modern medicine.

We humans also like to perceive the passage of time in units of seconds, minutes, hours, days, weeks, months, and years. We’ve created these units because they are comfortable, connected to the rhythms in the sky and in our bodies, and each is used to make sense of events both short and long. Here’s the critical point for the rest of the story—

One of our average humans sees 75 years x 365.25 days/year =27,394 days in their life

That’s amazing. That’s 27,394 days of getting up in the morning, eating, working, playing, relaxing, and going to bed. Put this way, the length of a single day is absolutely inconsequential relative to a human lifetime. Agreed? Good.

A Really Cool Diary

So let’s say I had this really cool diary with one page for every day of our average human’s life. It’s a single book with 27,394 pages. I could give it to you at birth and ask you to record your life one page—one day—at a time (with some help from a friend in your early and possibly later years). Like I said, one cool diary.

A Day in the Life of the Earth

Let’s say planet Earth was this large cosmic creature. She’s got a life expectancy of about 10 billion years, from her birth with the Sun nearly 5 billion years ago, to her ultimate fate when the Sun is in its waning years some 5 billion years from now (nope not telling).

Earth obviously has a lot to say, and SHE’s been keeping a diary since she was born. But she’s got it in far too many volumes, since each didn’t come with many pages, and they’re all old and worn out. Hey, I think a new diary is a perfect gift for her! I’ll give her one of my really cool diaries with 27,394 pages. I’ll help her move all her old diary entries into the new one so it will truly record her 10 billion year life. Why don’t we call each page a GEOLOGIC DAY (a Dr. Jeff made-up term.) And every Geologic Day is absolutely inconsequential relative to Earth’s lifetime. After all, Earth has 27,394 of them.

Every Geologic Day, Earth will write in her diary the comings and goings for that day. Here’s the next important point—

Every one of the 27,394 pages in Earth’s diary—each Geologic Day—is 365,000 years long.enough time for 14,600 human generations

How come? Easy: 10 billion years divided by 27,394.

Take a minute to process that.

I hope this gives you a new perspective for spans of time for Earth—called geologic time—relative to the time span for our fleeting lives.

So I give my friend the Earth one of my cool diaries. She likes it—her life all in one book. I also happen to be very close with Earth, and she’s letting me look at her diary. So here we are in the middle of her life and she just now finished her entry for day 13,697. She’s already written the first 13,696 pages (I helped her transfer the entries from her old diary with Apple Time Capsule.) Here now is her page 13,697—

Dear diary-

Today, as always, I’m going to keep a watchful eye across my surface. It’s an important responsibility being an oasis of life in a vast space. I’m very aware that all the countless forms of life living on me depend on a very delicate balance of surface conditions. Every Geologic Day, I hope I can avoid asteroids, comets, and super volcanoes, all examples of catastrophic events that have wreaked havoc with my sphere of life—my biosphere—in the past.

Today started out as pretty routine with lots of new things to see. I’m still watching those bipedal creatures that first appeared about 6 Geologic Days ago. Over the last few days, it looked like there were a few different species of them. But by late today I’m pretty sure there was only one dominant species left. I’m fascinated with them. They’re intelligent. They make tools.

Well, time to stop writing it’s just about the next Geologic Day. There’s only 35 Geologic Seconds left in this one (150 years to us humans). Wait … did you see that?! Carbon dioxide levels in my atmosphere just spiked! This just can’t be right! All of a sudden carbon dioxide is at the highest level it’s been in at least 2 Geologic Days (800,000 years) … maybe even 50 Geologic Days (20 million years)!

This is serious. Carbon dioxide might seem innocent enough—my diversity of life creates and uses it. But my neighbor Venus has an atmosphere that is 96% carbon dioxide, and while her surface should be about 125°F (50°C) at her distance from the Sun, the actual temperature is 880 °F (470 °C)—hot enough to melt lead. Carbon dioxide is a gas that induces a greenhouse effect on a planet, causing elevated surface temperatures, and in the case of Venus the effect is absolutely extreme. In my case, my biosphere is in a delicate balance, and even though carbon dioxide is a trace gas, a substantial percentage increase can cause dramatic changes in the environment.

IN AN ALMOST IMPERCEPTIBLY SMALL AMOUNT OF TIME—carbon dioxide in my atmosphere has skyrocketed by 60% over typical levels. Its increase is nothing short of—stunning. This is not due to natural cycles. No natural variation would happen this fast. This is the signature of a CATASTROPHIC EVENT. Some global scale, very short event that should be OBVIOUS. But I see no obvious crater, no super volcano … let me keep looking.

Wait. What’s happening now?! The temperature just spiked! Global temperature variation over the recent past shows “little ice ages” and warming trends, but what I’m seeing now is a SPIKE—a very quick change— that looks very different than those natural temperature variations. The global temperature is now CLEARLY INCREASING, and higher than it’s been recently (us humans currently have the ability to gauge it over the last 2,000 years), and it spiked at the same time as did the carbon dioxide.

This is very bad. Warnings are now coming in from everywhere—rapidly decreasing sea ice, rapid glacial melt. There has to be a cause. Something’s happened. Something’s different. This looks like the start of an irreversible change in the global environment. I’ve got to find out what’s happening before it’s too late for countless species on my surface. Let me keep looking and see if I can find something big that’s happened in this INSTANT in time … a trigger … something OBVIOUS.

Wait …. it’s … it’s the bipeds! OH NO … they’re everywhere! Their technology is EVERYWHERE—just in the last 35 Geologic Seconds! It’s an infestation!

They have got to be stopped. They’re supposed to be intelligent … maybe not. But I’ve got to try reasoning with them.

HEY YOU!! Look at the data!! Look at the data!! Quick! Quick!

What are you doing! Stop! Are you crazy?! Do you think you can load my atmosphere with those levels of emissions from your technology—in a blinding instant of time—and not impact me? Do you think my systems are capable of scrubbing the atmosphere that fast?  MY SYSTEMS DON’T WORK ON TIMESCALES OF 35 GEOLOGIC SECONDS!!

…not enough of them are listening

They’re too busy, too pre-occupied … with themselves.

They don’t seem to care if they are committing suicide. Their choice. But … they don’t have the right to take countless other life forms with them. I’ve got to put in an emergency call to Interplanetary Pest Control, or … tomorrow will be a very bad day.

(Note to reader: spread the word on climate change. I’d argue you have a duty to spread the word. You should Tweet this one up planet-wide. And be moved to leave a comment.)

To Teachers:

You can really make this a powerful visual demonstration in class. The life of Earth recorded on 27,394 sheets of paper is a challenge to demonstrate. But if you can borrow some cartons of xerox paper, with each carton containing typically 10 reams, then here is what I’d do. Each ream contains 500 sheets. So you need 5 full cartons (that’s 50 reams = 25,000 sheets) + 4 reams (another 2,000 sheets) + 394 sheets.

Without telling the class anything about what you are doing, have them take the reams out of the boxes (without opening them) and lay them out on the floor. Have them open one ream to see how many sheets are in it. In fact, have them count the sheets in the ream and take out the 394 sheets you need. Then:

• walk them through the concept of a single diary for an average human lifetime: they should calculate how many diary pages they would need if there is one page per day; then have them calculate how many sheets are on the floor—”oh, the number of days in a human lifetime!  WOW!!  That’s a lot of days for a human!”

• let them in on the idea of giving this diary to Earth, and assuming a lifetime of 10 billion years, have them calculate how many years of history are on EACH sheet—”365.000 years! No way!!” Then have them calculate the equivalent number of human generations on one sheet assuming 25 years per generation (a reasonable time from parent birth to child of parent birth)—”Can that be right? 14,600 generations!?”

• re-arrange the paper with half of it on one side of the floor to represent Earth’s history that is already recorded,and the other half on the other side of the floor representing Earth’s future history.

• then pick the single sheet of paper that represents the last 365,000 years of history, so that on this sheet, the final diary entry is the present. Lay it between the two groups of paper representing the past and future history of Earth.

Ask the class to think about this sheet of paper as a 24-hour clock. So at time 0:00:00, you’re at the beginning of the sheet, 365,000 years ago. At time 12:00:00 you’re in the middle of the sheet 182,500 years ago. At time 24:00:00 you’re in the present moment, where you all happen to be sitting in class.

Ask them to calculate the time on the clock when human civilization began (10,000 years ago, answer: at time 23:20:19); when the industrial age began (the age of fossil fuels; 150 years ago, answer: at time 23:59:25).

Have them look at world population growth noting what’s happened during the age of fossil fuels, the carbon dioxide level over the last 650,000 years, and the world temperature over the last 2,000 years. What is the data telling you?

• have them figure out how many sheets ago the dinosaur extinction took place.

• have them research Earth’s geological history, and figure out which sheets contain other milestones or important intervals in Earth’s history.

This should be MIND BLOWING! It is an experience your students will likely remember for a lifetime.

* * *

Image courtesy NASA, Johns Hopkins University Applied Physics Laboratory, and Carnegie Institution of Washington.

From Dr. James Hansen, Director of the NASA Goddard Institute for Space Studies, concerning this post—Public understanding of climate change depends on an understanding of time scales. Goldstein [Dr. Jeff] does a brilliant job of making clear the rapidity of the human-made intervention in the climate system, and the correlation of global warming with the appearance of technology powered by fossil fuels.

Image courtesy NASA, Johns Hopkins University Applied Physics Laboratory, and Carnegie Institution of Washington.

The year is 2064 and you’re telling students how Unmanned Aircraft Systems (UAS) first made debut flights to make measurements of atmospheric composition, way, way up in the atmosphere at 20 km from the ground and flying for over 30 hours non-stop. Today, this sounds like a Wright brothers’ story that your  teachers told you when you were young. The unmanned aircraft are now so commonplace that well-to-do families own at least one UAS for vacationing in the cosmos. The story sounds funny to the students hearing that NASA was just beginning to deploy UAS in field missions. NASA now have sophisticated UAS, which look like bats and have capability to fly anywhere anytime, and can be programmed on the fly to make any type of measurements needed by scientists.  Actually, NOAA now uses them routinely to monitor the global environment.

NASA Global Hawk (FS-098-DFRC)

The era of UAS in operational atmospheric research at NASA began in earnest in the year 2010. It was a very eventful year and remarkable in many ways. It was a year of El Niño (full name is El Niño-Southern Oscillation (ENSO)), which produced a lot of rain, floods, and other disturbances such as droughts in range of locations around the world. In the same year, earthquakes shattered records in Haiti where more than one hundred thousands lives were lost, while in Chile the 8.8 magnitude earthquake moved the entire city of Concepcion at least 10 feet to the west and shortened the length of the day by about one-millionth of a second. There was also so much talk about climate change, and the world political leaders could not agree on the steps needed to halt the rising CO2 levels that scientist had identified as the main cause of global warming.  So, NASA had just announced that in a period of six weeks between March and April, scientists would deploy an unmanned aircraft system named Global Hawk, for the first time to a field experiment named GloPac (Global Hawk Pacific Mission). The mission would take place out of Dryden Flight Research Center in California, USA, and would cover the entire offshore Pacific region with four to five 30-hour flights. The purpose of this experiment would be to support validation of a satellite known as Aura, which carried instruments for measuring gases such as ozone, carbon monoxide and nitrogen oxides. A ground based crew would guide the aircraft from the equator to the Arctic Circle, as remotely controlled scientific payloads on board collected data on key regions of the atmosphere important in climate change and ozone layer research. Researchers on the ground would be able to watch their data arrive in near real-time via satellite link, and could redirect the aircraft to certain phenomena or regions of interest along the flight track. The lead scientist would communicate with the world via Blogs and share almost near real time the excitement of the new adventure of deploying science instrument on UAS  for the first time in the history of NASA.

This first Earth science mission of the Global Hawk demonstrated the value of this unique and powerful resource to atmospheric science in the world. Those who witnessed the moment, can still remember the excitement.

Go, go, Global Hawk! Soar high!

Have you ever wondered how people test climate models?   We used to have a joke that climate modelers had the best job security – because no one would know if their models were right or not until after they died.

Actually, climate models are being tested all the time.  How is this done?  A variety of ways. Here, I’m going to discuss how climate models are tested, based on some things I learned recently at a symposium on Paleoclimates, sponsored by the Western Interior Paleontological Society (WIPS).  The figures are from one of the keynote addresses, by Dr. Caspar Ammann of NCAR.

First, climate models are tested by seeing if they can replicate the current climate.  Figure 1 shows one such simulation.  The image looks a lot like a satellite view of the weather on Earth – with the long strings of white looking like warm and cold fronts.  Also, notice the concentration of water vapor near the Equator. This is the Inter Tropical Convergence Zone (ITCZ), where air comes together from the northern and southern hemispheres, and then rises.   This is a “gut test” – the model results look right.  If you follow this simulation through the year (and we did at the NCAR Visualization Lab), you can see the progress of the Indian monsoon, and the formation of a couple of tropical cyclones (though you need pretty high horizontal resolution for that).  I should note that the simulation is for a “typical” year in today’s climate. That is – you won’t find a January 1 that looks exactly like this.

Figure 1. Total water vapor in a vertical column in the atmosphere. Areas with more water vapor look white, intense concentrations are orange. Courtesy James Hack, NCAR. (download at: http://www.vets.ucar.edu/vg/T341/index.shtml)

Climate models are designed to give us statistics about the weather, rather than specific real world weather events. For example, the climate model should be expected to do a reasonable job of reproducing the mean surface temperature over a season or over a year.  Such a comparison is illustrated in Figure 2.  The general temperature patterns are remarkably similar.

Figure 2. Surface air temperature. Top, from the Coupled Climate System Model, Version 3. Bottom, from observations. The relationship of colors to temperature is shown by the color bars to the right. Courtesy Caspar Ammann, NCAR.

Climate scientists also test parts of their models.  To understand this, let’s describe a climate model.  Like a weather model, the climate model solves equations for temperature, wind, water vapor, etc., on a three-dimensional grid of points.  For example, take a grid point 3,000 m above Dakar, Senegal.  Suppose the wind is out of the south, and the air is warmer to the south.  The model would “predict” that the wind would carry in warmer air, to warm the temperature by a specific amount.  Solar radiation, and longwave radiation (heat) from the ground and surrounding air layers would affect the temperature at this point, too.  Adding all these effects at each point will give a new temperature.  The same thing is done for wind, humidity, and whatever other variables the model is trying to predict.

Now imagine lots of these points – all over the Earth, and at heights from just above the surface to far up in the atmosphere.  Obviously, we need a computer to make all these predictions.  These predictions are made for specified time intervals, which vary with the grid spacing (and type of model).  The first set of values on the grid leads to a second prediction.  The second set of values on the grid leads to a third prediction, and so on.  For weather forecast models, the calculations are repeated for a few calendar days.  For climate prediction, the predictions can run for a thousand years.  (Of course the computer run will take a much shorter time than 1,000 years – otherwise the forecast wouldn’t be very useful!  To avoid confusion, scientists sometimes refer to “model time” (1,000 years) to contrast that with how long it took to run the model (much less)

We’d like these points to be as close together as possible, but the number of points is limited by the size and speed of computers, so the points are farther apart for climate models than for weather models.

Because of this, the effects of things like thunderstorms have to be estimated using what we call “parameterization schemes.”  If a thunderstorm went through our point 3,000 m over Dakar, the model would allow for that by changing the temperature (and wind, and humidity, etc.).

Climate models have also to account for changes in the ocean, and changes in the land surface, including ice and vegetation and soil.  The model will account for wet soil warming up the air more slowly than dry soil (but at the same time evaporation would transfer moisture from the soil into the atmosphere where it can later condense and release that stored heat), and solar radiation reflecting off an icy or snowy surface.   The amount of detail on the surface can vary from model run to model run.

And this leads to another way the models are tested – each of these parameterization schemes is tested.  Sometimes, observations are used.  These can be data routinely gathered using satellites, or data gathered in a field campaign focused on a specific phenomenon – like thunderstorms, or like stratus clouds to the west of continents.

Anytime observations are used, the model is tested for the “current” climate state, or its variability. But how can we be sure that the same model also might do a reasonable job for future climates when we expect things to be different?

For this, one option climate scientists have is to simulate past climates. Because we have some information about past climates, we can see how well models reproduce them.  We all learn that our climate has changed over the age of the Earth.  For example, North America and Europe have had repeated glaciations during the last couple million years.  Figure 3 shows an example of one such simulation, with temperatures compared to the climate simulation.

Figure 3. Comparison of a climate simulation to temperature estimates, for the last interglacial, about 130,000 years ago. On the left side are real world proxy-based reconstructions of maximum summer temperature (circles are land records, triangles are marine records), on the right side is a model simulation that was done applying information about the Earths orbital configuration of that time. (Adapted from Figure 2, from Otto-Bliesner, B.L., S.J. Marshall, J.T. Overpeck, G.H. Miller A. Hu, and CAPE Last Interglacial Project Members, 2006: Simulating Arctic climate warmth and icefield retreat in the last Intergaciation Science, New Series, v. 311, No 5768, ;1751-1753.)

How do we know how the temperatures changed during geologic time?  We use other evidence (referred to as “proxies.”)    Much of the dicussion at thew WIPS symposium was about this topic. Here are just a few ways:

1.     Measuring the ratio of “heavy oxygen” (Oxygen-18, or oxygen with an atomic weight of 18) to light oxygen (the “normal” oxygen isotope, with an atomic weight of 16).  Since “lighter” water molecules evaporate more readily at cooler temperatures, more of it rises into the atmosphere to form precipitation, which is stored in the ice sheets during ice ages.  Thus more “light” oxygen in ice means cooler temperatures.
2.    Counting the teeth on the boundary of leaves.  The number of teeth is related to temperature.
3.    Determining from fossil leaves and pollen what type of vegetation lived in a given area.  If these are for the same (or similar species) that live today, this provides information about the climate under which the plant grew.
4.    From the temperature range of the nearest living relative of fossil animals.
5.    Looking at the fraction of Oxygen-18 in foraminifera, tiny (usually less than 1 mm across) little animals with shells that lived primarily in the oceans.
6.    Looking at the type of insect damage in plants provides clues about how tropical the climate was.
7.    Structure of a specific type of molecule (tetraethers) is a strong function of temperature at the time of its formation.
8.    And many, many more…

Similarly, fossil evidence provides clues about how rainy it was.  For example, the minerals deposited in channels formed by roots vary with how well-drained the soils were, and hence how dry the soil was.  And fossils of lush, tropical plants are associated with rainy climates.

Simulations of these ancient climates aren’t always consistent with the data – but scientists are finding that comparisons with paleoclimates can lead to both improvements in climate models – and sometimes, a refinement in the observations!

Given that, I’m going to show you my favorite simulation, which puts modern day influences on climate in perspective.

Figure 4. Simulation of climate for the last century. Blue includes experiments where only natural forcing factors were affecting climate: volcanoes and solar output. The red/pink simulations also include the effects of changes in greenhouse gases and dust produced by humans. The black line is the observed temperature record. (dapted from Figure 2, of Meehl, G.A., W.M. Washington, C.M. Ammann, J.M. Arblaster, T.M.L. Wigley, and C. Tebaldi, 2004: Combinations of Natural and Anthropologic Forcings in Twentieth-Century Climate. J. Climate, 17, 3721–3727.)

From Figure 4, one obtains the current warming record only if the effects of greenhouse gases are included.

Climate scientists continue to test their models – and improve them.  This is being done through improving the parameterizations, and, with time, running at higher resolution (smaller grid sizes).  With these improvements, climate scientists should be able not only to improve projected global average statistics, but they should be able to look at future climates in different parts of the world. The Holy Grail (ultimate goal) of climate modeling then is if model can do both global trends and regional impacts in both mean but also in variability, including the information about changes in extreme events!

News media recently dubbed “Climategate” the release of a group of private emails between climate scientists in England and the United States that contained discussion that was interpreted by some news sources as manipulation of the data to produce a desired outcome.  These communications were taken from a server at the University of East Anglia, from an archive of a research group headed by Phil Jones, a well-known climate scientist.  The emails were intended to be private, but contained content labeled by some as professional cheating.  A summary of the Climategate scandal is here:

http://en.wikipedia.org/wiki/Climatic_Research_Unit_e-mail_hacking_incident

These emails contained negative comments about the research of certain “climate skeptics” such as Professor Patrick Michaels, a scientist who has consistently disagreed with the views of the Climategate emailers about global warming.

Labeling the purloined emails and their interpretation as “Climategate” suggests a parallel with the “Watergate” scandal of the 1970’s, a break-in to the headquarters of a United States political party, housed in the Watergate Hotel in Washington DC. That release of private records led to the resignation of the person the hackers had been trying to support, Richard Nixon, then President of the United States.  However, rather than compare Climategate to Watergate, as the media has, we might compare it to a scientific scandal, one that happened in the early 1700’s, nearly 300 years ago, namely Isaac Newton’s claim to be the inventor of calculus, against the counter-claims of a widely known mathematics Professor, Gottfried Leibniz.  For simplicity, and with some irony, we’ll label this older scandal “Calculusgate.” A nice discussion of this controversy is online on Wikipedia. Quoting from that Wikipedia article as we find it today, 15 December, 2009:  “… a bias favoring Newton tainted the whole affair from the outset. The Royal Society set up a committee to pronounce on the priority dispute, in response to a letter it had received from Leibniz. That committee never asked Leibniz to give his version of the events. The report of the committee, finding in favor of Newton, was written by Newton himself and published as ‘Commercium Epistolicum’ (mentioned above) early in 1713. But Leibniz did not see it until the autumn of 1714.   The prevailing opinion in the eighteenth century was against Leibniz (in Britain, not in the German-speaking world). Today the consensus is that Leibniz and Newton independently invented and described the calculus in Europe in the 17th century.”

At first sight, there appears to be a strong parallel between “Climategate” and “Calculusgate.”  That is, there developed a strong consensus led by the “establishment” that the truth about the origin of calculus was that Newton was the sole inventor, while Leibniz simply complained about Newton’s lack of rigor, and tried to push his own notation, and agenda.  In this, the Royal Society of London served as the “establishment” much like today’s Intergovernmental Panel on Climate Change (IPCC), which was anointed by the establishment with the 2007 Nobel Peace Prize.  Isaac Newton himself chaired the Royal Society study that issued a report that declared Newton himself to be the sole creator of calculus, without serious review of the claims of Leibniz, whom we might call the “calculus skeptic.”  The parallel here is that Phil Jones, former head of the Climate Research Unit of the University of East Anglia, appears to have been “cooking the books” to make it appear that his claims of global warming are the correct ones, without serious consideration of “climate skeptics” like Patrick Michaels and others that he was criticizing in the ClimateGate emails.  The emails seem to indicate that Jones and his colleagues even considered forcing out Journal editors that weren’t sympathetic to his research. So, whom should we believe, Newton or Leibniz?  Jones or Michaels?

But this Calculusgate analogy, like the Watergate analogy, is far from perfect. Climategate involved a group secretly hacking into nonpublic computers to purloin private data, which is?itself a crime. In that sense, Climategate is more like Watergate than Calculusgate, and perhaps like Watergate it could backfire on the hackers. Keep watching the news to see. Also, Newton’s scandalous behavior did not negate his fundamental contributions to science.  Indeed, Newton is still considered a towering figure in physics, having developed the basic laws of force and motion, light and gravitation. But Leibniz is also now viewed with reverence. Newton and Leibniz are both considered constructive pioneers in the development of calculus during the 18th century. Their different approaches are each considered to have been useful in different applications, now that the passage of time has led to a more balanced perspective.

However, the reputations of Jones and Michaels may not turn out to have equal luster after the coming century.  Each represents alternative views about what will happen to global climate in the coming 21st century.  Jones and IPCC forecast a steady continued warming at a rate primarily determined by the rate of humanity’s continued use of fossil fuels, and a resulting steady decrease in global ice volume, and rise in sea level.  Michaels and other non-establishment climate skeptics forecast no steady warming, but temporary warming alternating with periods of cooling, with the periods of warmth and coolness primarily determined by non-human natural changes in the Sun’s brightness, in volcanic eruptions, and in natural transfers of heat within the climate system.  It is likely that only one of these views will prove correct.  If the skeptics are correct, there is nothing that mankind can do but wait, and watch.  If Jones and the IPCC establishment are correct, mankind is increasingly becoming the main player in the drama of the global climate, and may not simply stand by, waiting and watching, but may agree on long-term policies that might reduce the rate and magnitude of the warming, and the resulting ice melt, and the ultimate height of the rising sea level.  It is important that you, all of us, decide soon which of these alternative viewpoints to take as your working hypothesis about climate change, and choose to act accordingly.

Science is “testing ideas using observations” (R. P. Feynman.)  This is an objective approach to learning about the world.  But one scientist cannot make all observations needed to test each scientific idea or hypothesis.  Therefore, many of our scientific opinions are based on which scientists we choose to trust. How do you decide whom to trust?  Of course, that’s an issue in much of our lives, not only in science.  We don’t trust when there’s evidence of a “cover-up.”  We demand “transparency” in our governments, our businesses, and most of all, our personal relationships.  Scientists rely on personal relationships as much as anyone else.  Science relies on evidence and direct observations as much as possible, but as a practical matter, science must also rely on trust, and on good judgment about who to trust.

So science needs both trust, and skepticism. Science differs from pure skepticism, and from other philosophical approaches to knowledge, in its emphasis on observations, and on the process of developing and testing hypotheses.  Science encourages skepticism, but goes beyond skepticism.  It encourages development of alternative hypotheses, and values only those hypotheses capable of being tested by new observations, perhaps requiring new technology.  Climate science is not purely an experimental science, where we can decide the big questions with a few well-chosen experiments.  It is an observational science, in which we are living inside our own global experiment, and must adapt to the climate as we attempt to better understand it.  Our Earth’s climate is itself the experiment that matters most.  You cannot make all the observations needed to make up your mind about what is causing climate change.  But you can talk to your neighbors, to your grandparents, to your colleagues across our planet, and you can read what the experts write, and decide for yourself who is most reliable. Your decisions about our future climate will hopefully be as well informed as possible. Our future climate may depend on that. That is why your participation in GLOBE matters.

Can you think of examples in your own experience when you became less trustful of someone?  More trustful?  What led to changes in your trust?  How do you decide who or what to believe?  Do you base your beliefs mostly on what your friends tell you, or what you read, or on your own observations?  Why do you think the media labeled this incident “Climategate”? What do you think news media in 1700 might have called the “Newton-Leibniz” scandal? To see how one organization responded to Climategate, read this “statement on climate change”:

especially the section entitled “How will climate change in the future?”  Then read the organization’s reasons for not altering their climate change statement after “Climategate” which the organization refers to as the “CRU Hacking Incident”:

What do you think about this organization’s reasons for not altering their “statement on climate change” after the news about Climategate?  In particular, discuss these statements with your friends, family, teachers and other students:

• “As with any scientific assessment, it is likely to become outdated as the body of scientific knowledge continues to grow, and the current statement is scheduled to expire in February 2012 if it is not replaced by a new statement prior to that.”
• “The beauty of science is that it depends on independent verification and replication as part of the process of confirming research results.”
• “Even if some of the charges of improper behavior in this particular case turn out to be true — which is not yet clearly the case — the impact on the science of climate change would be very limited.”
• “The AMS encourages ethical behavior in all aspects of science and has established a record of affirming the value of scientists presenting their research results “objectively, professionally, and without sensationalizing or politicizing the associated impacts.”

Write several sentences to describe your own policy about how to decide about the truth of scientific claims.  Consider both the case when you have made some of the observations yourself, and the case when you are mainly relying on the observations of others.  Share your policy with your teachers and classmates, and see how your policy compares with theirs.

The following two pictures of the same place were taken on different days. Can you explain why the upper picture is clear but the lower one is not?

Two pictures taken from the same place at Texas Tech University, Lubbock, Texas, USA show: (upper) the bluish sky on a clear spring day in 1998, and (lower) the hazy sky on a dusty day (6 April 2001) at about 5:30 PM local time (pictures downloaded from http://www.atmo.ttu.edu/dust.html)

As we all probably learned from our science classes, the air within our atmosphere is naturally composed of gases, including nitrogen (N2), oxygen (O2), carbon dioxide (CO2), and several others. The atmosphere also frequently contains water vapor (H2O), which is water in its gaseous form. In addition to gases, the atmosphere contains very small particles in solid or liquid form, called “aerosols”. Liquid aerosol particles are in the form of viscous (or oily) droplets rather than water droplets.  Individually, aerosol particles are practically invisible to the human eye, because most of them are 10 microns or less in size (1 micron or micrometre = 1 metre divided by 1000000). By comparison, the human hair has a diameter of between 17 and 181 microns. Certain types of atmospheric aerosols (typically on the order of 0.2 microns in size) can serve as a nucleus upon which water vapor condenses to form clouds. Such aerosols are referred to as cloud condensation nuclei.  However, when there are high concentrations of aerosols in the air, especially near the surface of the earth where people can breathe them, we say that the air is polluted. In fact, the agents of air pollution (or pollutants) can occur either as unhealthy gases mixed up with the air or as aerosols floating in the air. People that monitor the air quality in different places often report the aerosol content of the air to the public in terms of the concentration of particles by mass per unit volume of air (typically expressed in units of micrograms per cubic meter). For air-quality purposes, aerosols are often referred to as PM10, which means all particulate matter (PM) in the atmosphere whose aerodynamic diameter (apparent diameter while floating in the air) is 10 microns or less. A subgroup of the PM10 often identified in air-quality monitoring is called PM2.5, which means all particulate matter whose aerodynamic diameter is 2.5 microns or less. There are several different types of aerosols depending on the materials or chemicals they are made of and where the aerosols come from. People and animals inhale aerosols in the air they breathe. The tinier the particles are, the easier they can enter the lungs and cause serious harm to our health. Therefore, for a given aerosol type, those in the PM2.5 size group are more harmful than the larger size group.

Aerosols can come from many different sources, some of which are natural and others anthropogenic (i.e. caused by human activities). Some of the main aerosol types and their sources are: (i) chemical pollution aerosols from industries, cars, trucks, and other modes of transportation, (ii) smoke from large and small fires, (iii) dust blown by wind from bare ground surfaces, (iv) sea salt from ocean sprays caused by waves resulting from the action of the wind and other forces that cause sea motion, and (v) volcanic aerosols from eruptions of volcanoes. As you may have guessed, chemical pollution aerosols are almost all caused by people, because of many of the things we do to enjoy life and move around. Smoke aerosols are to a large extent caused by people who set fires to forests, bushes, trash, or anything that produces smoke, although in certain places smoke originate from fires caused by lightning strikes or large accidental events. Dust aerosols are mostly generated by wind, but sometimes people produce dust while moving or conducting certain activities in dusty places. In fact, when we do anything to destroy vegetation anywhere and leave the land bare, we are also helping to provide favorable conditions for dust generation. Sea salt aerosols are mostly natural, and only a very tiny proportion is indirectly produced from human activities that cause waves in the ocean, such as fast moving boats and ship. Volcanic aerosols are entirely natural and often lofted very high in the atmosphere away from where people can inhale them. Ironically, aerosols caused mainly by people, such as chemical pollution and smoke, are mostly in the PM2.5 size range, which are the most harmful to people.

How can we know when there is a high concentration of aerosols in the atmosphere? One simple way is to look up in the sky when the sun is up. If there are no clouds, the sky should look bluish (that is, sky blue) when the air is clean. If the sky is hazy (that is, not bluish) when there are no clouds, then there must be a high concentration of aerosols in the atmosphere. In this case, the color of the sky will depend on the source, type, and amount of the aerosol along our line of sight to the sky. The reason for this is that the Sun’s light is made up of (electromagnetic) waves distributed across a wide range of wavelengths forming a spectrum. Only light whose wavelength is in the visible range (approximately 0.38 to 0.75 microns) of the spectrum can be seen by the human eye, and represent the different colors of the rainbow (violet, indigo, blue, green, yellow, orange, and red: as arranged in ascending order of wavelength). When the Sun’s light is travelling through a clean atmosphere that has no cloud, the air molecules scatter the shorter wavelengths, of which the eyes are most sensitive to the blue light, because air molecules are smaller than visible light wavelengths. This phenomenon was discovered by the 1904 Nobel Laureate in physics, Lord Rayleigh, and is known as Rayleigh scattering. This is why clear sky looks blue during the daytime, except during sunrise or sun set. When the sky is cloudy, the clouds appear white. Since the cloud droplets are much larger than the wavelengths of visible light, the cloud scatters all visible wavelengths almost equally and appears white because the sum of all colors in the rainbow is white. Aerosols in the atmosphere can scatter and/or absorb lights of different wavelengths to various degrees depending on the aerosol type, amount, and size distribution. Therefore, large amounts of aerosols in the atmosphere cause the sky to look hazy in different shades of grey or pale yellowish to brownish colors, depending on the position of the sun relative to the observer.

As a practical exercise, look up the sky one or more times a day for at least a week and take pictures of what you see. Remove the pictures that contain thick clouds. Out of those that have no clouds, or with just a few clouds and much free sky space, try to separate the pictures in which the sky is blue from those in which it is not. Those where the sky is hazy must contain large amounts of aerosols. Try to identify the photo with the largest amount of aerosols. How much aerosols were present on this day with respect to the other days?  Compare this picture carefully with that of the blue sky day and discuss it with your friends, teachers, family, and possibly community, to try to identify the possible source(s) of the aerosols. What could all of you do (if anything) to reduce or stop such aerosol at its source(s)? We know that high concentrations of aerosols in the atmosphere are harmful to people’s health in many ways and it is the responsibility of us all to keep the air clean. In future blogs, we shall discuss many other aspects of aerosols, such as: how far they can travel from their sources, how long they can stay in the atmosphere, how they leave the atmosphere and where they go, how they are measured from the ground, or from aircraft or satellite, how they relate to clouds, and what they can do to the weather and climate.