By Charles Fredricks
5 or 10 years: The amount of time we may have to lock in transition of electric power generation, heating and cooling, and transportation away from carbon based fossil fuels to renewable energy, to avoid civilization-ending disaster.
50 years: The time lag roughly between when we will feel the effects in the climate system of the carbon emissions we are generating now.
positive feedback mechanisms, 3: Systems in the biosphere that have a tipping point that could move warming beyond humanity’s ability to control.
1) the albedo effect: Arctic and Antarctic ice reflect more solar radiation back into space than dark blue ocean. The more ice melts into dark blue ocean, the more solar radiation the ocean absorbs, which warms the ocean, which melts more ice.
2) methane: Methane (CH4) has 100 times ± the heat trapping effect of CO2 over the first couple decades in the atmosphere. Twice as much carbon as all the carbon currently in the atmosphere lies frozen in the form of methane deposits beneath Arctic tundra and the ocean floor. As tundra and the ocean warm, the methane is released. The more methane in the atmosphere, the more it warms, warming ocean and land, which melts more methane.
3) ocean acidification: Atmospheric CO2 dissolves into oceans, rivers and lakes, forming carbonic acid. The increase of dissolved CO2 lowers ocean pH, causing the death of reefs, home to thirty percent of all the fish, and the death of phytoplankton, the bottom of the marine food chain. Allowed to continue, ocean life will die, and the ocean’s ability to buffer atmospheric CO2 will reverse, becoming another source releasing CO2 into the atmosphere.
.8∞C: The amount of warming we have experienced thus far, over pre-industrial levels. All the effects on storms, drought, flooding, forest-fires and species migration (bark beetle wiping out forests for eg.) have been the result of less than one degree Celsius of warming.
2∞C: A decade ago the international community settled on 2∞C of warming over pre-industrial levels as the limit of safety, a compromise between what scientists thought might be safe and what economists and politicians thought could be economically and politically feasible, considering the extent of transition necessary, and the varied responsibilities of developing and developed nations. Fresh data indicates the climate system is more sensitive as the changes are coming more rapidly than predicted, while nations have reneged on promises to decrease emissions. Allowing 2∞C of warming may be too much to avoid crossing the tipping point threshold of irreversible climate change.
4∞C: The point at which the climactic changes will have wiped out civilization across most currently inhabited areas of the globe, due to drought, sea level rise, extreme temperature.
6∞C: The point where we can say with some certainty we will have crossed the tipping point.
5-7∞C: Where we are headed by the year 2100 under our current emissions pathway of business as usual, if we do not change course.
10-14∞C increase: The amount of temperature rise expected by 2300 if the tipping point is crossed.
565 gigatons of carbon: The amount of carbon we can add to the atmosphere, and have slightly worse odds than playing Russian roulette with a six-shooter, of staying below 2∞C warming.
2,795 gigatons of carbon: The estimate of current known proven coal, oil and natural gas reserves: more than five times the amount we can safely burn.
Stock price: The oil companies’ stock price based on the latter figure will likely collapse [go to disinvestinvest.org]
20,000,000: Number of refugees created by climate change last year: more than all the wars combined (UN figures). This number will go up every year as sea level rise and drought cause further population displacement, resource shortages, and political instability.
100% renewables by 2030: is possible: http://inhabitat.com/study-reveals-renewable-energy-could-support-all-of-civilization-by-2030/
PHOTO CREDIT: https://www.flickr.com/photos/craigoneal/