As
global average temperature increase exceeds about 3.5 oC, model projections suggest significant extinctions (40 - 70 % of species assessed) around the globe.
Let's also look at the specific IPCC quote that Mr. Romm furnishes us with: «As
global average temperature increase exceeds about 3.5 °C [relative to 1980 to 1999], model projections suggest significant extinctions (40 - 70 % of species assessed) around the globe.»
The IPCC's Fourth Assessment says, «As
global average temperature increase exceeds about 3.5 °C [relative to 1980 to 1999], model projections suggest significant extinctions (40 - 70 % of species assessed) around the globe.»
Not exact matches
Global average temperature increase will
exceed the recognized «guardrail» limit of 2 degrees Celsius.
... Polar amplification explains in part why Greenland Ice Sheet and the West Antarctic Ice Sheet appear to be highly sensitive to relatively small
increases in CO2 concentration and
global mean
temperature... Polar amplification occurs if the magnitude of zonally
averaged surface
temperature change at high latitudes
exceeds the globally
averaged temperature change, in response to climate forcings and on time scales greater than the annual cycle.
Aware of the broad scientific view that the
increase in
global average temperature above pre-industrial levels ought not to
exceed 2 degrees C, we support an aspirational
global goal of reducing
global emissions by 50 percent by 2050, with developed countries reducing emissions by at least 80 percent by 2050, and recognizing the critical importance of development, including poverty eradication, in developing countries.
The draft states: «We recognise the scientific view that the
increase in
global average temperature above pre-industrial levels ought not to
exceed two degrees centigrade.»
Approximately 20 to 30 percent of plant and animal species assessed so far are likely to be at
increased risk of extinction if
increases in
global average temperature exceed 1.5 to 2.5 °C.
Release of ECS methane is already contributing to Arctic amplification resulting in
temperature increase exceeding twice the
global average.
Global average temperature increases of 0.74 °C are already documented, and
temperature increases in some areas are projected to
exceed 3.0 °C over the next decade.
The overwhelming majority of the world's scientists agree that any
increase in
average world
temperatures that
exceeds 2 degrees Celsius (3.6 degrees Fahrenheit) above the pre-industrial era — some opt for a rise of no more than 1.5 degrees Celsius — will alter the
global climate system drastically.
In July 2009, Prime Minister Stephen Harper signed on to a G8 summit declaration recognizing the broad scientific view that the
increase in
global average temperature above pre-industrial levels ought not to
exceed 2Â °C.
The latest report by the IPCC, the international organization tasked with assessing the science of climate change and its impacts, predicts that in order to keep the
increase in
average global surface
temperature under 3.6 degrees Fahrenheit (2 degrees Celsius), total future CO2 emissions can not
exceed 1 trillion tons.