Wind speeds across the globe have increased rapidly over the past decade signalling good news for the renewable energy industry, according to scientific research published today in the journal Nature Climate Change.
The findings show that a trend of decreasing wind speeds since the 1970s – a phenomenon known as global terrestrial stilling – has now been reversed with a significant increase observed since 2010, scientists at Cardiff University said.
The university is part of an international team that analysed data taken between 1978 and 2017 from over 9000 weather stations across Europe, North America and Asia.
Analysis showed that the global mean annual wind speed decreased at a rate of 2.3% per decade during the first three decades, beginning from 1978.
They calculated that if this trend were to continue to the end of the century, global wind speed would reduce by 21%, thus halving the amount of power available in the wind.
Yet, the findings showed that since 2010, wind speeds have increased at a rate three times greater than the decreasing rate before 2010.
If this trend were to persist for at least another decade, wind power would rise to 3.3 million kilowatt-hours in 2024, an overall increase of 37%.
Cardiff University School of Earth and Ocean Sciences Adrian Chappell said: “This rapid increase in global wind speeds is certainly good news for the power industry.
“The reversal in global terrestrial stilling bodes well for the expansion of large-scale and efficient wind power generation systems in these mid-latitude countries in the near future.”
The research also examined potential reasons why wind speeds had declined and then increased.
Previous studies proposed that the slowing down was linked to increased ‘roughness’ on the surface of the Earth, caused by urbanisation and vegetation changes, which acts almost like a filter and slows wind speeds down.
However, the team said it demonstrated that the phenomenon is linked to changes in large-scale ocean and atmospheric circulation patterns.
The strongest drivers of wind speed were the Pacific Decadal Oscillation, the North Atlantic Oscillation, and the Tropical North Atlantic Index, the research said.
The researchers believe that increasing wind speeds should continue for at least another decade, as it takes around a 10 years for changes in the wind patterns to occur.
But, they noted, the patterns in the future will probably cause a return to declining wind speeds and so anticipating these changes should be a priority for the wind power industry, the team warn.
Chappell said: “The development of renewable energy sources is central to keeping warming below 2 degrees C.
“One megawatt of wind power reduces 1300 tonnes of carbon dioxide emissions and saves 2000 litres of water compared with other energy sources.”
The study was led by a scientist from Princeton University in the US now based in the Southern University of Science and Technology, Shenzhen, China.