Changing the lives of survivors and volunteers worldwide
How does Climate Change Influence Disasters?
Climate change is causing an increase in the number and intensity of severe weather events worldwide and making communities more vulnerable to the effects of those events.
While it is difficult to say whether an individual severe weather event is caused by climate change, it is possible to observe a trend in weather related disasters. Oxfam illustrates this trend in their report, “The Right to Survive”.
“Climate-related disasters are becoming more and more common, and have more than doubled since the 1980s. Reported floods alone have increased four-fold since the beginning of that decade. 2007 saw floods in 23 African and 11 Asian countries that were the worst in memory."(source)
In the same period the average number of people reported as affected by climate-related disasters has risen from 121 to 243 million a year – an increase of over 100 per cent. Oxfam International predicts that by 2015, the average number of people affected each year by climate-related disasters may grow by a further 50 per cent to 375 million. (source)
The increases in typhoons and precipitation result from the increased evaporation and warming oceans. On a warmer earth, water evaporates more quickly, leading to greater concentrations of water vapor in the lower atmosphere and, by extension, heavy rains.
While there have always been rainy seasons, these rains are becoming more frequent, intense, and unpredictable, resulting in more severe and frequent floods.
Likewise, while hurricanes and typhoons can be difficult to study as their numbers vary greatly from year to year, these storms draw their energy from the oceans. Warmer oceans can lend more power to forming typhoons and hurricanes and lead to more powerful and frequent storms, as explained by the US Climate Change Science Program:
‘It is likely that the annual numbers of tropical storms, hurricanes and major hurricanes in the North Atlantic have increased over the past 100 years, a time in which Atlantic sea surface temperatures also increased. It is very likely that the human induced increase in greenhouse gases has contributed to the increase in sea surface temperatures and in the hurricane formation regions.’ US Climate Change Science Program Assessment, June 2008.1
At the same time that typhoon and hurricane prone parts of the world are experiencing more frequent and intense storms and floods, other areas are experiencing more frequent and intense droughts, again due to increased evaporation.
In other words, climate change is not just causing one type of disaster to increase while eliminating another. It is causing an increase in severe weather events of all types.
While increasing the frequency and intensity of severe weather events, climate change also makes communities more vulnerable to the effects of those events by weakening communities and increasing vulnerability.
Climate change increases vulnerability and the events which cause disaster. By acting on both sides of the equation "Disaster = Natural Event + Vulnerability", climate change affects all parts of disaster and devastates lives.
1Weather and Climate Extremes in a Changing Climate, North America, Hawaii, Caribbean and US Pacific Islands’, Synthesis and Asessment Product 3.3, June 2008.
