« Назад

It's 2019- When does your mosquito season begin?

We’ve discussed how the mosquito story is a climate story and a human story, looking at climate history and human history. Contemporary climate change is now playing a role in the expansion of vector borne disease- not only in space but also in time.

How many days are mosquitoes active in your city? You can find out by using this Disease Danger Day tool:  http://www.climatecentral.org/news/us-faces-a-rise-in-mosquito-disease-danger-days-21903. I live in Colorado, so I selected Denver, and found out that since 1970 there are now 10 more days a year on average when mosquitoes are active. By active, we mean that mosquitoes are  flying, biting, laying eggs and larvae and pupae are developing in water. How many more days are in your city, compared to 1970? Or maybe, you live in one of the lucky cities that have fewer days when mosquitoes are active. Either way, let me know and share your observations in the Science Cafe!

We know that different species of mosquito exhibit different temperature tolerances. For instance, Aedes aegypti, the yellow fever mosquito that can transmit a variety of diseases, including dengue, chikungunya and Zika, they require temperatures between 10- 39 degrees Celsius (50-102 degrees Fahrenheit). Aedes albopictus, the  Asian tiger mosquito, which can transmit the same diseases, have a slightly different ecological tolerance range:  15-35 degrees Celsius (59-95 degrees Fahrenheit). Culex mosquitoes, species of which are implicated in transmitting West Nile Virus thrive between 10-35 degrees Celsius (50-95 degrees Fahrenheit).  Within those ranges there are also ideal temperatures for the different stages of the life cycle, so data will show some variability in response to other factors that are also involved.

What are some of the other factors that contribute to mosquito survival, reproduction and development? We know that precipitation, humidity and land cover play a role, perhaps you can think of some other factors. Together, these factors combine to determine the time of first appearance of mosquitoes in your region. And because these factors vary year by year, the first day of appearance of mosquitoes in your area will also change from year to year- and from mosquito species to mosquito species.

GLOBE Mission Mosquito campaign participants, we are interested in finding out when you first see mosquitoes in your neighborhood! We want to build a phenological  (first appearance) map, or seasonal map, showing when the mosquito season starts in every part of the U.S. Some of our research questions are: how different is this year’s map from the map that shows the average over several years of when we see first appearance of mosquitoes? What vector species do we see first, and where?

What other questions can you think of? Do you have any hypotheses about what you think you will see?  Let us know by posting your questions in the Science Cafe!

Map of projected first appearance of mosquitoes, based on monthly minimum temperature data.  Map data from Anthony Arguez, lmke Durre, Scott Applequist, Mike Squires, Russell Vose, Xungang Yin, and Rocky Bilotta (2010). NOAA's U.S. Climate Normals (1981-2010). [Monthly Minimum Temperatures]. NOAA National Centers for Environmental Information. DOl:10.7289/V5PN93JP [Accessed December 2018]. Courtesy Andrew Clark, IGES.



Please log-in to post comments