We usually associate drought with extremely dry weather condition, or the lack of rain or
precipitation. Recently, I found out that there is another weather condition called “wind
drought”, the slowing down of wind speed. It’s now a reality, according to some experts.
The blowing of the wind happens so naturally that we don’t notice changes in it, except probably for
strong winds during typhoons.
According to an article published in the Horizon, the European Commission Research
and Innovation Magazine, the average terrestrial wind speed has decreased by 0.5 kilometers per
hour (0.3 miles per hour) every decade, according to data starting in the 1960s. It is a
phenomenon called “stilling”.
Here’s one particular case. Through summer and early autumn 2021, Europe experienced
a long period of dry conditions and low wind speeds. And the consequence? Wind farms
produced 18 percent of the United Kingdom’s (UK) power in September of 2020, but in
September of 2021, that percentage plummeted to only 2 percent. To make up the energy gap,
the U.K. was forced to restart two mothballed coal plants.
According to the Global Wind Energy Council, there is now 743 GW of wind power
capacity worldwide. A decrease in wind speed, even just a small one, will reduce the capacity of
wind turbines to generate electricity. This will trigger a shift back to thermal power plants that
use fossil fuel, which will result in more greenhouse gas emissions.
Wind drought has other consequences other than the drop in wind energy generation.
Plants for instance, will be affected. Some seeds are dispersed by the wind, and others rely on the
wind for pollination. So, the absence or slowing of wind speeds will affect plant population.
It might also affect their growth. The blowing of the wind on young plants helps make their stems
strong. Air quality will be affected too. Wind helps drive away air pollutants. Note that after a
storm the air is clean because all the pollutants like dust, smoke, emissions from vehicles and
factories have been blown away.
Stagnant air will impact health, and might even contribute to
heat waves. There are also serious implications of wind changes in areas like agriculture and
hydrology, basically because of the influence of wind on evaporation.
So what’s the reason for this “wind drought”? Among the leading theories is that
urbanization and changing land use is increasing the roughness of the land surface, slowing
down winds. Another possible cause is climate change.
The latest Intergovernmental Panel on
Climate Change (IPCC) report suggests that average wind speeds over Europe will be reduced by
8%-10% as a result of climate change.
One of the strategies to address global warming is stop the use of fossil fuel and shift to
renewable and environment-friendly energy sources like solar and wind. However with “wind
drought”, wind energy may not be that reliable anymore. That’s bad news.