An Independent School • Grades 5-12

by Allistair Y. ’20

Senior Allistair Y. reflects on his experience with the Lakeside Summer Research Institute (LSRI). For more information on the LSRI, see teacher Michael Town’s introductory blog.

Last year, arrays of small temperature sensors known as “iButtons” were deployed on both the southern ascent of Mount Baker by students on an outdoor trip and the field adjacent to the Allen-Gates building on the Lakeside campus. My job this summer was to develop code to examine the data collected by the Lakeside campus iButtons, as a way to prepare for our retrieval of the Mount Baker iButtons. Once we collect the Mount Baker temperature arrays, we will be able to simply run my code on them to review the data.

By comparing the data from sensors placed in direct sunlight with data from sensors placed in the shade, I wanted to determine if temperature difference can tell us anything about cloudiness. I began the project with Figure 1, which essentially represents pure iButton data from two of the Lakeside sensors. Figure 2 was the next step; by subtracting the covered sensor’s temperature points from the exposed sensor’s temperature points, I was able to produce a histogram, or graph representing the distribution, of temperature differences. The red bars represent all iButton data and the blue/purple bars represent just the 12 p.m. data points. From this histogram, we can see that at night, there are many more occurrences of the sunlight sensor being colder than the shade sensor. This seeming anomaly demonstrates that in the absence of sunlight, the shade sensor is generally a little more insulated than the exposed sunlight sensor.

Finally, using the new temperature difference data and solar radiation from a weather station at the University of Washington, I was able to produce Figure 3, a plot of daily solar radiation vs. temperature difference. With an R2 value of 0.59 (with 1 indicating a perfect correlation and 0 indicating a very poor correlation), it seems that temperature differences of sunlight and shade can be used to indirectly estimate the cloudiness.

The long-term goal of this project is to find out more about the climate of Mount Baker, an environment that is potentially more vulnerable to the effects of human-driven climate change given its high altitude. There is currently no reliable temperature or cloudiness data set for Mount Baker; perhaps Lakeside will have the first usable data set for this prominent feature of the Northwest landscape.

Figure 1. Temperature data with daily 12 p.m. points from 12/17/18 to 3/3/19.

Figure 2. Distribution of temperature differences between direct sunlight and shade data. The red bars represent all iButton data and the blue bars represent daily 12 p.m. points.

Figure 3. This plot examines the correlation of temperature difference (Tsun - Tshade) at 12 p.m. daily with solar radiation—which is directly related to cloudiness—also at 12 p.m. daily.