(Image of flooded region in Bangladesh. Source: www.worldculturepictorial.com)
According to the International Displacement Monitoring Group, more than 30 million people were forced to flee their homes as a result of extreme weather during 2012.
Droughts, storms and floods caused this massive displacement, one many times the impact of warfare over the globe. Hardest hit regions included Africa, where 8 million people were forced to flee their homes due to extreme weather. That said, even well developed countries suffered major dislocation events resulting in an unusually high number of displaced persons — topping 1.3 million in 2012. The largest number came as a result of a climate change induced Superstorm Sandy which rendered about half a million people homeless in the US.
Over the past few decades, instances of extreme weather have more than doubled, according to reports from the US National Climate Data Center. This amped up weather is driven by increasing temperatures and rising atmospheric water vapor content brought on by human caused climate change. In addition, erosion of Arctic sea ice has led to a disruption of the northern polar jet stream, resulting in more blocking patterns that enhance the chances for droughts, floods, and blizzards. The large north-south dips in the jet also enhance the possibility for powerful hybrid storms, like Sandy, to emerge with ever-greater frequency.
Global monitoring groups expect the numbers of displaced persons to increase as human-caused climate change intensifies. Recent reports from climate expert Lord Stern highlighted in the Guardian called attention to this risk. Stern warned of high risks that temperatures could rise by 5 degrees Celsius or more by the end of this century. Such heating, Stern noted, would have terrible impacts:
“Hundreds of millions of people will be forced to leave their homelands because their crops and animals will have died. The trouble will come when they try to migrate into new lands, however. That will bring them into armed conflict with people already living there. Nor will it be an occasional occurrence. It could become a permanent feature of life on Earth.”
The news comes as worldwide CO2 levels begin to exceed 400 PPM — a dangerous threshold that could melt most polar ice and increase global temperatures by 3-4 degrees Celsius if fossil fuel emissions aren’t halted soon. Sadly, CO2 emissions are only rising, with the world on track to reach 550 PPM by mid-century and 900+ PPM by 2100. Such CO2 rises would be nothing short of catastrophic.
Through the resulting large temperature increases, wet bulb temperatures will be expected to begin to exceed 35 degrees Celsius over growing regions for increasing periods of time. During such instances, these regions will be rendered practically uninhabitable to mammal life, including humans. Human beings and livestock will be effectively heat-driven, first from isolated regions and then from growing areas of the globe as time moves forward. This impact will over-lap the already powerful and growing impacts that result from climate change induced storms, droughts and floods.
With world CO2 levels at 400 PPM, we are already in the period of time when weather events can be expected to cause increasing instances of dislocation. Depending on the rate of global ice loss and ocean heat uptake and on whether or not fossil fuel emissions are curtailed and eliminated soon, instances of heat lethality are likely to become more prevalent and an ever increasing concern after 2035-2050. At the same time, rising sea levels are also expected to begin to have an increasing affect on low-lying regions, especially in areas most prone to cyclone activity. Under business as usual fossil fuel emissions, by 2100 almost all regions will be severely affected by dislocation events.