by Jenna Mallon (’18)

Wind speed is an important area of climate study because it has lasting effects on climate variations. In the Southern Hemisphere, studies involving wind speed are unavailable, despite there being research on air temperature and precipitation. As a result, Luiz Felipe N. Cardoso from the Department of Meteorology at the Federal University of Rio de Janeiro and a team of researchers conducted a preliminary analysis of Southern Hemisphere wind speed patterns in order to determine if there was any statistical significance to them.

Using data from the National Oceanic and Atmospheric Administration’s Nation Model Archive and Distribution System, the team used mathematical programs to create regression models of the wind speed trends. The data used was taken from January 1961 to December 2008, and wind speeds were calculated using the GrADS software. The data was then subjected to two non-parametric statistical tests: the Mann-Kendall and the Sen’s Bend. The tests concluded, with 95% confidence, that there was a statistically significant increase in wind speed, particularly around the equator. Overall, the majority of the Southern Hemisphere has experienced increasing wind speeds, except for a few areas in the South Pacific that showed decreases.

As this was a preliminary analysis, more research still needs to be done in this area for solid results. In order to increase the dependability of the statistical models, a study involving the coupling of different data sets is necessary. Additionally, there is still no concrete explanation for these wind speed trends, so further research into this should be conducted.

References:

1. F. N. Cardoso, W. Luiz Silva, M. G. A. Justi da Silva, Long-term trends in hear-surface wind speed over the Southern Hemisphere: a preliminary analysis. International Journal of Geosciences 7, 938-943 (2016). doi: 10.4236/ijg.2016.77070.
2. Image retrieved from: https://upload.wikimedia.org/wikipedia/commons/thumb/9/9c/Earth_Global_Circulation_-_en.svg/2000px-Earth_Global_Circulation_-_en.svg.png