You know know a litte bit about what we do so here's a little bit of why we do what we do...
The International Tundra Experiment, called ITEX, is an international collaboration of scientists and universities from all over the world. There are 19 ITEX experimental sites in more than 11 countries. Every country that lies within the Arctic Circle is particpating in ITEX including: United States, Sweden, Canada, Norway, Iceland, Russia, Greenland, and Finland. There are three sites in Alaska: Barrow, Atqasuk, and Toolik. All the ITEX sites have both control plots and experimental plots that are designed to raise the temperature of the tundra about three degrees. Ground warming is done in most places using open-top chambers that act as miniature green houses.
Researchers then record data about plant growth and phenology by measuring leaf heights and documenting the plant life cycle of selected plants within each plot. All the data is recorded in a standard manner so that researchers in Russia will understand what is happening in Alaska and vise versa. The researchers can then pool all their data together and analyze what's happening to the plants in regards to warming temperatures. They are trying to predict what will happen to the plants as the tundra regions get warmer.
Here are some of the questions they are asking:
1. Will there be a change in the types and numbers of each species?
2. Will plants from warmer areas "move in" and outcompete native plants?
3. Which plants are best suited to deal with the change in temperatures?
4. Will the plants that prefer colder temperatures be able to adapt to a warmer climate?
5. Will the growing season dates change as the temperatures warm?
To test these questions, the scientists had to design an experiment that would keep everything the same, except the temperatures of the plants, so they had to leave the plants in the tundra soil because removing them would add another variable to the mix. That's why they designed the OTCs.
The OTCs trap heat and raise air temperature 1 to 3 degrees Celsius, depending on outside temperature, humidity, cloud cover, wind, and many other factors.
Compare this control plot in Barrow Dry to the experimental OTC plot below. Which one has more plants? In which one are the plants taller?
Compare this OTC experimental plot in Barrow Dry to the control plot below. Which one has more plants? In which one are the plants taller?
The OTCs warm the temperature of the air surrounding the plants about three degrees. They are open on top so the plants can still be pollinated by insects. They don't receive as much wind though because the fiberglass wall of the OTC shelters the plants a bit. There is also some condensation buildup on the inside walls at times as well. At the end of the growing season, in late August, the researchers dismantel the OTCs so the plants receive the exact same winter weather as the control plots.