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Maybe I'm missing something here, but if we can determine whether or not the system is in thermal equilibrium, does that not address the question of global warming once and for all? After all, it's not called Global Warming for nothing. It's actually impossible to determine if the Earth is warming unless you use a method that integrates all the effects. The Earth is no different from any other thermodynamic system.
I appreciate that taking Ice cores from Greenland is a good way of analysing the gaseous content of the atmosphere for the globe but..... I feel that the measurements for temperature could be very misleading as they are very localised. Is there anyway of correlating what this readings show and what was happening in the Sahara for example? And how do these temperature readings fit in with global averages?
I found this link quite informative on current climatic modelling systems; http://www.gcrio.org/CONSEQUENCES/fall95/mod.html
Very Probable:(3) Higher surface temperatures will cause an increase in the average precipitation over the globe. This comes about because temperature affects the rate at which surface water is evaporated (to return to the ground in the form of rainfall and snow). While the connections between temperature and precipitation rates are well understood, the distribution of changes in precipitation over the Earth is less certain. [...]Probable:( Continental dryness will increase at middle latitudes in summer in the Northern Hemisphere. The basis for this prediction is the fact, cited earlier, that higher temperatures lead to much higher rates of evaporation: in net effect, the increase in evaporation will on a regional basis exceed the accompanying increase in rainfall. The amount of drying is qualified, however, by several factors that are not well represented in models. These include the movement of evaporated moisture from place to place through atmospheric circulation; the effects of changes in ground cover due to the response of vegetation to increased carbon dioxide; the role of aerosols; and interactions between the land surface and the atmosphere, including the storage of wintertime precipitation in soils. (9) Rain and snow at high latitudes will increase as the amount of moisture in the atmosphere is increased. The freshwater that is added there by precipitation could alter the deepwater circulation of the oceans, which is driven in part by differences in the salt content of different parts of the ocean and which in turn affects climate. Additional precipitation could also affect the size of the polar ice caps, and hence perturb sea-level. Uncertain:(12) Changes in climate variability will occur. However, the exact nature of changes in climate variability due to greenhouse warming is as yet not well defined. All models predict a possible reduction in wintertime variability in warmer climates; it is also commonly predicted that thunderstorm activity should increase as a result of the increased moisture content of the atmosphere. The frequency of El Niñ o events could change as a result of a global warming, as could the frequency of atmospheric "blocking" events that set up persistent weather patterns that last weeks to months at a time.(13) Changes in the climate of regional-scale areas (from the size of large metropolitan regions to the scale of states or small countries) are likely to be quite different from the global average. We have only a very limited capability to estimate changes expected in the climate of any specific region. The spatial resolution of climate models is, as yet, too coarse to incorporate effects such as regional land characteristics, surface contours, and local hydrologic conditions, even though these factors are known to be important. Regional changes in climate can differ from global changes, but the nature of the probable differences is uncertain. [...](16) Interactions between climate and vegetation may modify the magnitude of predicted greenhouse warming, but whether these effects will amplify or diminish climate change is as yet uncertain. The limited assessments that have been made suggest possible feedbacks due to climate-induced changes in vegetation, such as the replacement of high-latitude tundra by vegetation more characteristic of temperate latitudes, or the displacement of forests by grassland. Other climate impacts can result from the direct effects of enhanced carbon dioxide on plant growth, from impacts of tropical deforestation, and from the effects of plant productivity on atmospheric chemistry.
Very Probable:(6) Global warming will cause sea level to rise. This is expected as a consequence of three temperature-related changes: the physical expansion of sea water as the ocean temperature increases, the partial melting of mountain glaciers, and changes in the extent and thickness of the Antarctic and Arctic ice sheets.
I found this site very informative about the subject. http://climate.nasa.gov/
So is it time to ignore the sceptics? []
I think I tried this one before and got shot down in flames. However, if at first you.....We must have a pretty good idea of the thermal energy that's being put into the Earth from all sources. We also know that the Earth radiates energy into space.Energy in = energy out - Happiness!Energy in ≠ energy out - Unhappiness!Sooooo, how can we measure the energy out bit? I was wondering if we can determine that from really far away by taking the Earth's temperature. If you get far enough away, all the localized variations are integrated into a single value. If we know the temperature, we should be able to determine the energy being radiated.If this were to actually work, it would seem to provide us with the sort of data we really need.