The data that convinced the scientific community (1999):
Simplest Prediction is increase in global mean temperature. Can We see evidence for this in the Data?
This is best seen by doing a geographic analysis of tempearture trends:
This was followed by mid-century cooling, again thought to be natural:
Which was then following by likely human induced warming:
Distribution of Responsibilities:
The Importance of Methane:
Current concentration of CO2 is 360 ppm
Current concentration of CH4 is 1.8 ppm or 25x1.8 = 45 ppm CO2 equivalent. This is 12% of CO2 concentration and its growing 2.5 times as fast.
Methane Removal Mechanism (some estimates suggest the methane residence time is up to 12 years so there is no short term equilibrium control):
CH4 + 2O2 CO2 + 2H20
A major concern, a positive feedback loop:
Note, however, that "catastrophic" release of CH4 during period of Ice Ages may be the natural way that the Earth accelerates from a glacial period:
Known Hydrate deposits. Found typically in continental shelf where marine organisms (microbes) actively feed on carbon and carbon related productes to produce methane in the sediments.
Modeling the Climate System:
The climate system is complicated with all kinds of couplings:
In addition, the role of increasing clouds is crucial Net Cooling or Warming? There is general consensus that cloud cover will increase as the capacity for the atmosphere to retain water increases with increasing temperature. Cooling vs warming depends critically on cloud droplet size and location in the atmosphere. Increasing high, cold clouds increases reflectivity and may lead to cooling. Increasing low, warm clouds, increases precipiation and heat retention.
What do the most reliable (?) models show? slices.
Here is the equivalent data for the oceans