Burn all the fossil fuel, and here's what happens: study

Monday, September 14, 2015, 1:38 PM - Vancouver, Montreal and Halifax under water. Prince Edward Island simply gone and Nova Scotia becomes an island. This is the future we're looking at if we burn all of Earth's currently accessible fossil fuels.

The current losses from Greenland's ice sheet, the melting of West Antarctica's glaciers, sea ice loss in the Arctic and thermal expansion of the warming oceans are all contributing to sea level rise - the tune of about 20 centimetres rise since the beginning of the 20th century.

This is already impacting on Canada's coastal communities, especially when it comes to the effects of storm surges, however according to a new study, if we continue to burn fossil fuels unchecked, and burn all oil, gas and coal we currently know is available, it will cause a collapse of the Antarctic Ice Sheet that will completely overwhelm the contribution of these other sources.

"To be blunt: If we burn it all, we melt it all," lead author Ricarda Winkelmann, a Junior Professor of Climate System Analysis at the Potsdam Institute for Climate Impact Research in Germany, told the New York Times.

The study conducted by Winkelmann and her colleagues used a computer model known as PISM (Parallel Ice Sheet Model), to estimate the response of the Antarctic Ice Sheet to the temperature rises expected if we continue to burn fossil fuels unabated - referred to as the "business as usual" and even "worst case" scenario.

Based on their findings, releasing the 10,000 gigatonnes of carbon stored away in the oil, gas and coal we can currently access - which has been locked out of the carbon cycle for millions of years - would result in the near complete loss of the Antarctic Ice Sheet, resulting in 58 metres of sea level rise in the next 10,000 years.

That is a very long time, however what's striking about this finding is the fact that half of that melting, and thus roughly 30 metres of sea level rise, will likely occur within the first 1,000 years.

"If we were to burn all attainable fossil fuel resources, this would eliminate the Antarctic ice sheet and cause long-term global sea-level rise unprecedented in human history," Winkelmann said in a statement. "This would not happen overnight, but the mind-boggling point is that our actions today are changing the face of planet Earth as we know it, and will continue to do so for tens of thousands of years to come. If we want to avoid Antarctica to become ice-free, we need to keep coal, gas and oil in the ground."

Effects on Canada

What would nearly 60 metres worth of sea level rise do to Canada?

According to data collected by NASA's Shuttle Radar Topography Mission (SRTM), Vancouver would be inundated by seawater, as would the surrounding communities and those along the last stretch of the Fraser River Valley.

Credit: floodmap.net

As the ocean filled up the St. Lawrence Seaway from the east, much of Quebec City would be flooded, creating a new island out of the highlands from Old Quebec to Parc Cartier-Roberval.

Montreal's Mount Royal, along with the "jagged peaks" of the tall buildings of the city's downtown core, would rise above the still waters of an expanded - and now 30-40m deep - Lake St. Lawrence.

Credit: floodmap.net

The most widely-felt effects of this kind of change would be in Atlantic Canada. Most coastal communities in Nova Scotia and New Brunswick would be under water, including Halifax, Yarmouth, Sydney, Moncton, both Saint John and St. John's, and nearly the entire province of Prince Edward Island would be lost beneath the waves.

Credit: floodmap.net

Further north, the shorelines of James Bay and Hudson Bay retreat by around 100 kilometres or more in some areas. Coastal communities, including Churchill, will be lost to the rising water.

Credit: floodmap.net

All together, this equates to over 20 per cent of Canada's population - nearly 8 million people - displaced from their homes. As Canada's population grow in the decades, centuries and millennia to come, even more people will feel the impact.

Underestimated results?

Penn State climate scientist Michael Mann commented on the study in an email to Mashable.com's Andrew Freedman, writing:

"I'm not convinced that the ice sheet model fully accounts for the complex dynamics relevant to predicting ice sheet collapse on timescales of decades to centuries, which I consider to be most relevant. There is considerable empirical evidence that has been provided over the past couple years that we are likely already now committed to at least 3 to 4 meters of sea level rise from West Antarctic Ice loss, due to warming already in the pipeline and the destabilization of the ice shelves, which support the inland ice, due to southern ocean warming that has already taken place."
"It seems to me that the model is actually underestimating the near-term prospects for sea level rise given ongoing fossil fuel burning, and that’s actually what I’m much more worried about."

According to Freedman, study co-author Ken Caldeira agrees with Mann's assessment that the study may be underestimating the impacts, however, as Caldeira explained: "I'd rather be accused of being overly conservative than overly alarmist because this is alarmist enough as it is."

Sources: New York Times | Potsdam Institute for Climate Impact Research | Floodmap.net | NASA | Mashable | Wikimedia Commons