Global warming
Regional Warming
We must consider the temperature change
of different regions to assess
global warming danger.
Arctic warming
The most important region by far is the Arctic - because of all the carbon the Arctic holds, till now safely cold and frozen. In the case of the Arctic the temperature increase has not stalled- it has gone on increasing at a rapid rate. Now the Arctic is warming 3X the global average. That means increasing Arctic methane emissions, and also CO2 and nitrous oxide. This increased warming of the Arctic is what matters most because it can lead to the planetary catastrophe of GHG feedback rapid global warming and runaway climate change.
RADIATIVE FORCING (total heat in the climate system) correlates directly with the total increase in atmospheric GHGs. The NOAA converts the two into a GHG Index which provides a measure of the increase in GHG heat in the whole climate system. It is the best single index of global climate change to use.
Climate Emergency Institute
Global warming is the increase in global average (land-sea) (year average) surface temperature, as a consequences of radiative (heat) forcing increase caused by anthropogenic (human sourced) greenhouse emissions (IPCC)
June 1988 New York Times Global Warming Has Begun, Expert (NASA James Hansen) Tells Senate
There was never any question in the science that emissions of greenhouse gases would cause global surface warming, increasing with the amount and duration of emissions. The very atomic structure of GHG molecules (dipole) determines that as fact. Since the first IPCC assessment in 1990 that has been certain.
'We are certain of the following:
• there is a natural greenhouse effect which already keeps the Earth warmer than it would otherwise be
• emissions resulting from human activities are substantially increasing the atmospheric concentrations of the greenhouse gases carbon dioxide, methane, chlorofluorocarbons (CFCs) and nitrous oxide These increases will enhance the greenhouse effect, resulting on average in an additional warming of the Earth's surface The main greenhouse gas, water vapour, will increase in response to global warming and further enhance it' (IPCC 1990 1st Assessment WG1 Science Executive Summary).
Ocean heat: global warming says nothing about the >90% of GHG heat that goes to ocean warming. The heat in the oceans is a commitment to higher degrees of future global warming, even with rapid reductions of emissions.
Acid aerosol global cooling: Global warming is
reduced by fossil fuel air pollution acid aerosol cooling.
This is also a commitment to increased future global
warming because industrial fossil fuel emissions
have to be stopped to stabilize the climate-
and ocean acidification.
Amplifying feedback emissions: global surface warming will (and is) cause additional feedback emissions from the warming planet surface. That is an extra global warming commitment resulting from the above two commitments. The obvious example of an amplifying feedback is the increased forest fires.
As predicted decades ago the nothern hemisphere is warming faster than the
southern (which has more ocean) and the Arctic is warming fastest of all (Arctic amplification).
Extreme rapid Arctic warming (3-4X rest of planet) is a planetary emergency because the largest sources of carbon which will be released by more with warming - are in the Arctic, like permafrost.
Rapid warming of Europe and N. America is a planetary emergency- the world's best food producing regions, where heat waves and drought are increasing.
The long term trend of global warming is obvious accelerating rate of increase, and recently rate has increased faster
2023 warming was a big record at 1.45°C
Unprecedented rate of atmospheric
CO2 increase
drives accelerating increase
of global warming
Summer warming
Global warming does not provide what we most need to know- that is summer temperature increases over land
The NASA map shows warming hotspots for 2002 confirmed by trends
May 2024 Record +1.52°C
12 Months of records 11 Months at/above 1.5°C
There is unequivocal evidence that Earth is warming at an unprecedented rate (NASA)