March 2012 - Great Global Investigation of Climate
March 2012 GGIC Summary
One of the extensions of the Great Global Investigation of Climate is to take not only air temperature but soil temperature measurements. As expected, there is a relationship between soil temperature and air temperature. While you may not be able to capture this relationship measuring once daily, you can see this relationship by measuring all temperatures every 15 minutes, like some GLOBE schools do.
Stone Child College, located in Box Elder, Montana, USA, uses a HOBO data logger to send automated air and soil temperature data into the GLOBE database. The image below shows air and soil temperature data from Stone Child College collected on 15 and 16 March 2012. This site is a great example of the lag (or offset) between of soil temperature at depths of 5 cm (blue line), 10 cm (green line) and 50 cm (purple line) and air temperature (red line). Notice the slight variation in the 50 cm depth – the temperature fluctuation would be seen over a monthly-seasonal time scale as opposed to daily. Also, notice the two axes – the left axis corresponds to the soil temperatures, which are significantly lower than the air temperature.
Using the same dates, the next image comes from Ramey School in Ramey, Puerto Rico, USA, who also uses a HOBO data logger. What's interesting about this site is how close the air temperatures are to the soil temperatures. This is due to Puerto Rico's closer proximity to the Equator and less dramatic seasonal fluctuations. But even with the closer temperatures, there still is a lag time between daily maximum air temperature and daily maximum soil temperature.
Each IOP provides a great opportunity to explore air temperature, soil temperature and precipitation and their connections to different GLOBE variables. How could you use your GGIC data to explore your local environment? Be sure to join us for our next IOP, which runs from 1-30 June.