The Link Between Climate Change and Extreme Weather Events Recently, we’ve seen a high frequency of devastating natural disasters. For instance, Hurricane Irma and Maria, the monsoon floods of Bangladesh, the Californian wildfires and mudslides and the so called ‘Bomb Cyclone’ over the east coast of the USA, that produced record low temperatures in the region. Whilst it is true that hurricane seasons are normal and floods and fire are part of nature’s cycle, it is also feasible that climate change is fueling more intense weather patterns and plays a part in triggering weather related disasters. It’s time to look at the evidence. By Richard Forsyth
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ven for those who believe in it and understand its significance, climate change is sometimes miscomprehended as a challenge we need to control in a future sense. The truth is that climate change is happening – it’s a process we are experiencing today. It stands to reason we should notice some changes in the weather. The Intergovernmental Panel on Climate Change (IPCC), comprised of the world’s most well-regarded experts in environmental fields, released a press release way back in November 2014 confirming ‘that climate change is being registered around the world and warming of the climate system is unequivocal’. Thomas Stocker, Co-Chair of IPCC Working Group said: “Our assessment finds that the atmosphere and oceans have warmed, the amount of snow and ice has diminished, sea level has risen and the concentration of carbon dioxide has increased to a level unprecedented in at least the last 800,000 years.” Only four years since that press release, the concentration of carbon dioxide in the atmosphere, as of January 2018, reached an alarming 408 parts per million – that’s the highest in around 3.6 million years – since a period known as the middle Pilocene, which had concentrations of carbon dioxide over 400. Obviously, in that era, the problem was not manmade but it’s known that our industrial activities are accelerating warming at an alarming rate. As a result, it’s estimated that around 800 million people are now vulnerable to climate change impacts. The IPCC predicted greenhouse gases in the atmosphere will likely increase land surface temperatures, leading to droughts. Such a change would also, they speculated, fuel intense cyclones with high wind speeds, create wetter Asian monsoons and significant mid-latitude
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storms. We could expect major floods, sea level rises and killer heat waves. Apart from the death, destruction and cost of extreme weather events, there would also be migration of populations escaping disaster. Of course, some of those ‘future’ weather predictions reflect the daily news reports we see today. So, is climate change already at play with weather events and can we expect more intense weather as the norm?
More rain and more heat It’s important to realise that global warming creates very volatile weather systems. A study published in Nature Climate Change in 2015, revealed that global warming in the last century has meant that extremes in heat that occurred once every 1,000 days, happen around five times more often. If we do manage to keep the global temperature limited to a 2 degrees C rise, which is an aim for many governments, we can still expect 60% more extreme rain events and 27 extremely hot days on average, in any given place on the planet. If we carry on going beyond a 2 degree C global temperature rise, we can expect sustained, widespread, very dangerous weather related phenomena. The fact is, it’s getting hotter each year on average. According to data by NASA, 2017 was the second hottest year on record, without an El’ Niño – and average global temperatures show that the top 10 warmest years recorded have all occurred since 1998.
How climate change fuels extreme events So far, the oceans are absorbing around 90% the world’s excess heat, hence, ocean temperatures have been rising consistently for the last three decades. When oceans absorb heat, they expand, causing sea
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