Here’s a look at my latest article read. I’ll be doing four this week considering I fell behind last week, follow my articles for some good reads.
This article by Thomas L. Mote addresses the impact of snow in the variance of temperatures across The United States. Let’s take a look:
Summary:
Mote introduces the topic of snow cover in the northern states of The United States in relation to the atmospheric temperatures. Study of this topic began back in 1963 with Namias and they initially discovered that snow impacts about 10%-20% of the monthly temperatures. Mote says his study looks primarily at, “the depression of daily mean maximum and minimum surface air temperatures across North America. . .” (2009).
Mote identifies that snow is more likely on days that would be cold regardless of snowfall. The main attempt of this study is to, “remove the effect of temperature changes above the boundary layer on the surface air temperature depression because of snow cover” (2011). Looking at the snowfall in correlation to the atmospheric temperatures poses a larger challenge in removing the variables of areas that are experiencing cold temperatures with no correlation to the amount of snow that is seen. However, in regions that do show significant response of snowfall, temperature depressions are a relative max at 3.2 degrees celsius for “shallow” snow and 4.6 degrees celsius for “deep” snow.
By using relative temperature to control temperature, we eliminate half of the findings that used only surface temperature readings. Mote also acknowledges the other variables of solar elevation, cloud coverage, and melting rates within the studied regions in order to appropriately study the snow’s direct impact without external forces.
Furthermore, the idea of snow-covered albedo is addressed in relation to forest cover. Mote describes, “It is a particularly useful proxy in this study, as it directly measures the effect of forest cover and other land surface features, such as lakes and other vegetation, on the surface albedo during periods of deep snow cover” (2019).
Finally, the study concludes by stating that after removing the temperature changes outside of snow coverage, the average of depression in temperature as a result of snow is 4.5 degrees celsius in the highest quartile of “maximum snow-covered albedo”. All in all, the study rings true that snow coverage alone does account for a notable change in atmospheric temperature, and when combined with the other temperature change variables, the atmospheric and surface temperatures are lowered.
3 Things for Future Study:
- Study limitation – “The primary limitation of both studies was that they did not isolate whether the temperature differences were solely because of snow cover or partially as a result of the tendency for snow cover to coincide with days that would be cold otherwise.” – how could this limitation be overcome and isolate the variables to avoid including data that’s cold regardless of snowfall in conjunction with days that were cold purely as a result of snow.
- Study boundaries – “However, one must exercise caution in making such a comparison between a 1° latitude 1° longitude grid cell that includes many stations, both urban and rural, to Baker et al.’s single station located on a farm field inside a major metropolitan area” – why is it important to avoid using an area with more stations? Wouldn’t the more cross-analysis be vital in ensuring days that were cold regardless of snow coverage?
- Snow age – I would like to look more into the “metamorphosis” of snow as it ages and the “grain size” increase in relation to the “snow’s albedo”. I would like to become a bit more familiar with the lifespan of snow and what happens to its potential and interaction with air as it matures and compacts.
Modern Meteorology:
I believe this article will help to shed light on how snowfall accumulation could impact the true surface temperatures in the winter and move toward further analysis of why at certain temperatures, snow accumulation doesn’t impact the surface temperature enough for noting. This seems to be a topic that is often missed for the most part and many just acknowledge snowfall but don’t examine what it means for the temperatures surrounding it. I like how their cross analysis of Baker et. al (1992) for their constant variable repetition became the main part in their choosing of locations on which to base their study, as well as which variables to look for when attempting to prevent corrupt data. Going forward I would expect meteorologists to begin examination of how snow really affects the atmosphere it’s in. Sadly, this is purely an idea that is tailored to the northern states and the southern would have to adopt a modified study that looks at small snowfall accumulation if they wanted to test their own impacts.
