FAQ - Instruments
A number of instruments, supplies, and pieces of equipment are needed to conduct the GLOBE measurement protocols properly. Many of these can be purchased from suppliers, while some can be made by students or individuals in the school community. Specifications for instruments have been developed by scientists in order to ensure accurate data collection while also being affordable for schools. It's important to emphasize that schools are not required, or expected, to collect data using all protocols; therefore it's important for the teachers to develop an implementation plan including which measurement protocols would fit best within the local environment, time available, and the class curriculum.
All GLOBE instrument specifications are described within the Toolkit (pdf) and represent the minimum specifications necessary to collect scientifically valid data. GLOBE schools may use instruments that meet or exceed these specifications. For example, the GLOBE specifications for pH paper call for a range of 2 to 9 pH units. A pH paper with a range of 1 to 14 exceeds specifications and may be used by GLOBE schools.Over 50 different protocols have been developed within the four GLOBE investigation areas of Atmosphere, Hydropshere, Biosphere, and Pedosphere (Soils). Some of the protocols are regionally specific and some serve as alternatives to each other. These protocols are meant to serve as options for schools to implement the protocols that compliment the activities they are covering in their curriculum.
The GLOBE Program does not endorse any particular supplier, and will identify in a similar manner all companies believed to offer instruments required for GLOBE. It is important that you contact any supplier you are considering as a source for your school's instruments prior to ordering the instruments to verify that the instruments meet current GLOBE specifications.
In order to locate the list of suppliers, visit: www.globe.gov -> "Do GLOBE" tab -> select GLOBE Teacher's Guide -> go to the "Instrument Resources" link -> then select your region from the bottom of the page.Several of our suppliers provide the same GLOBE instrument, and the prices vary. Suppliers sell individual items as well as complete kits. You will want to check each one for the best price and availability.
The GLOBE Program Office is not able to loan out specific scientific equipment due to the size of the program; however, some partners have this capability. For example, some partnerships have purchased GPS units and loan them to the teachers they train. Please contact your nearest partner to inquire about the possibility of borrowing equipment for short periods of time.We also suggest contacting local organizations, companies, and/or other teachers, parents, etc., who could share equipment that they have, such as their own GPS unit. Contacting a GPS manufacturer (such as Trimble or Magellan) to find out if they have educational lending programs may lead to successful acquisition of GLOBE equipment, thereby enabling school participation. In addition, some GLOBE teachers in many cities across the U.S. have reported receiving donations from their local WalMart Stores as part of WalMart's support of local schools. Please contact them to see if they have such a program in your location.
From a security point of view this makes sense, but from a scientific point of view this creates a whole series of problems that may not be resolvable in correcting the data. First, and most obvious, depending upon the composition of the roof, there will be drastic differences in temperature. A lot of schools have a "crushed rock" roof, which not only reflects daytime heat (causing warmer daytime temps), but absorbs and re-radiates heat at night (causing warmer temps until about midnight). Daytime temps can exceed over 100 degrees F, depending upon the roof type and exposure.
Another parameter that an affect temperature is wind. Due to the turbulence and "up-slope" caused by the building, the passage of air through the shelter may change drastically.
Rainfall is also problematic, since splash-back from the roof or adjacent walls into the gauge can occur, particularly under heavy rain conditions. Due to the wind problems, a wind screen is highly recommended around the gauge. Measuring snow (which is difficult under normal exposure) should not be done on a roof, because of wind effects.In summary, research quality environmental data cannot be collected from rooftops. If there is no alternative, then document the site well and record distances, rooftop composition, surrounding obstacles (including other roof lines), and instrument specifications. Some bias may be removed, but removing "heat island" effects is a difficult task. We can send you some references for siting exposure if it will help.