Yale Environment 360: It is becoming increasingly common to hear very knowledgeable people say that the possibility of
holding average global warming to under 2 degrees Celsius is slipping away from us.
Not exact matches
Many governments believe that
holding the
average global temperature rise caused by man - made
warming to 2 degrees Celsius above preindustrial levels gives the world the best chance to avoid dangerous climate change.
After all,
warmer air can
hold more water, and some research suggests
global warming could increase California's
average rain and snowfall.
This is the difference between countries» pledged commitments to reduce emissions of heat - trapping greenhouse gases after 2020 and scientifically calculated trajectories giving good odds of keeping
global warming below the threshold for danger countries pledged to try to avoid in climate talks in 2010 (to «
hold the increase in
global average temperature below 2 °C above pre-industrial levels»).
Consider the quasi-official
global goal (codified, for example, in the Copenhagen Accord) to
hold total planetary
warming to 2 °C (Earth surface
average) above pre-industrial levels.
The upper 3 meters of the world's oceans
hold more heat than the entire atmosphere, so continual ventilation of just 10 meters of
warmer subsurface water will affect the
global average for decades.
The IPCC reports have guided the European Union in formally adopting a specific goal of
holding global warming to no more than 2 degrees Celsius (3.6 degrees Fahrenheit) above the
average pre-industrial temperature of the mid-19th century.