Humanity can build a better tomorrow and limit the worst effects of climate change, but only if we take decisive action today, says the head of the United Nations.
The Intergovernmental Panel on Climate Change (IPCC) published the last part of its Fifth Assessment Report last weekend. The report is a synthesis of the three previous parts of the fifth assessment on the science, impacts and mitigation of climate change.
The report notes that warming of the climate system is now "unequivocal," with the warming seen since the 1950s being unprecedented in the last 1,000 years. Researchers were now about 95 per cent certain that at least half of the warming since 1950 was human-caused.
Climate warming has already caused increased droughts, fires, windstorms, tree deaths, coral bleaching and shifts in animal ranges, the report notes.
Even with all currently announced emission reduction efforts, the world is still on course to see another 3.7 to 4.8 degrees of warming by 2100, with an outside chance of 7.8 degrees.
Research suggests that four or more degrees of warming will result in "substantial species extinction" and "large risks to global and regional food security."
To have at least an even chance of limiting warming to two degrees, the world will need to reduce its greenhouse gas emissions by about 40 to 70 per cent by 2050 relative to 2010 levels and get to near or below zero levels by 2100.
Human influence on climate change is clear and clearly growing, said UN Secretary-General Ban-Ki Moon at a press conference in Copenhagen. With clear and decisive action, we have the means with which to avoid its worst effects and build a better and more sustainable world.
"Inaction on climate action will cost much, much more."
Science has spoken, and there is no ambiguity in its message, Moon said.
"Leaders must act. Time is not on our side."
Stark message
Researchers have done more studies on climate change in the last seven years than they have in the last 20, which gives this report a much more solid scientific base than previous ones, said University of Alberta sociologist Debra Davidson, one of the lead authors of the mitigation section of the fifth assessment report.
"There really is no ambiguity here anymore," she said.
The world will need to get at least 80 per cent of its electricity from renewable, nuclear or carbon-capture sources by 2050 if it wants to stay below two degrees of warming, the report notes (referring to the amount of warming generally thought to be manageable).
Alberta is a fossil-fuel economy and will have an extremely tough time meeting its obligations to avert climate change, Davidson said. That will have consequences for our international reputation and our ability to sell our products abroad.
But the impacts of climate change – which include more severe floods like the ones that recently hit Calgary – will also have severe effects on our farm, forest and tourism industries if unaddressed, she continued.
"There's a tremendous amount we could be doing here that we're not," Davidson said.
The province should crank up its investment in adaptation measures for the farm/forest industry and boost its support for household-level renewable energy, Davidson said. Residents should take steps to reduce their emissions from heating and transportation.
"The best bang for your buck in our province is more insulation," Davidson noted.
St. Albert resident Kelly Gray said her family has cut its electricity and gas use by about 75 per cent.
"We've got LED lights throughout the home," she notes, triple pane windows and solar hot-water panels on the roof. They also located their home so that they could walk to work, school and store, and built it using super-insulated straw bales.
"We generally don't consume any gas at all for five to six months of the year," she said, which reduces their gas bill in those months to $50 of administrative fees.
The synthesis report can be found at ipcc.ch.
