Recent studies estimate that even for conservative
global mean temperature increases, between 11 % and 34 % of species alive today could be threatened with extinction.
If species can move freely to new locations then the risk of local extinction decreases from around 25 % to 20 % with a 2 °C
global mean temperature rise.
If you look at the increase in
global mean temperature over the last fifty years, the vast majority of that is associated with human activity and the burning of fossil fuels.
CO2 emission has nothing to do
with global mean temperature as its patterns before and after mid 20th century, before and after wide spread use of fossil fuel, are nearly identical.
The graphs, therefore, give a fair indication of whether
global mean temperatures at or near the surface have been rising or falling over the past five or ten years.
For example, with some uncertainty, just about 50 per cent of the coral reefs may remain intact if the increase in
global mean temperature does not surpass 1.2 degrees.
A central conclusion of the report is that it is more effective to assess climate stabilization goals
using global mean temperature change as a primary metric, rather than atmospheric concentration levels.
Whereas emphasis to date has been on how these climate forcings
affect global mean temperature, the report finds that regional variation and climate impacts other than temperature deserve increased attention.
Because the locations and measurement practices of weather stations change over time, there are uncertainties in the interpretation of specific year - to - year
global mean temperature differences.
These weights allow for an objective, statistical prediction of
global mean temperature fluctuations arising solely from SST - associated internal variability within a given model.
If as suggested here, a dynamically driven climate shift has occurred, the duration of similar shifts during the 20th century suggests the
new global mean temperature trend may persist for several decades.
Maybe as those adjustments are done that the global basket of vital indicators should include an improved measure of
global mean temperature along with other indicators.
Three of the four global average temperatures indeed are decreasing in their trends (although the
actual global mean temperatures are still warmer than the previous decades).
For those who question whether the series
on global mean temperature are themselves products of a scientific conspiracy, here is yet a further check.
Unless otherwise specified, this chapter refers to
global mean temperature change above 1990 - 2000 levels, which reflects the most common metric used in the literature on key vulnerabilities.
Phrases with «global mean temperature»