As you probably suspect, I glean reams of news stories related to the Global Warming theory. It goes without saying that much of it is errant nonsense. It is again time to spell out the facts that are facts.
1 The Northern Hemisphere has warmed. We know that because the Arctic has a longer spring and summer. A direct result has been the opening of the two northern sea routes for the first time. Also glaciers are retreating all over the northern hemisphere. That pretty well confirms that this is a warm spell. Even the number fools who note that 2008 is the coolest year in the past five point out that still means that it is above average and has been above average for five years. We need seriously below average now to reset the averages back to normal. So yes it is actually much warmer in the Arctic.
2 The Southern Hemisphere has cooled. Glaciers are growing. The amount of cooling involved is either a mirror image of the northern warming or a very large fraction thereof. It is colder and thankfully, we do not try to have billions live there.
3 External drivers such as excess CO2 and solar variation have been presumed to alter global temperatures. The scientific support for either proposition is tenuous. For CO2 it was for ten years clearly coincidental. Since then for ten years it has been contrary. The solar variation idea is also potentially coincidental but more compellingly so for the two specific cases that exist.
4 It is not obvious that Northern Europe is a viable proxy for the Globe. Again we have the present situation in which a clear northern warming trend is been countered by a southern cooling trend. This is an actual expectation for an invariable heat supply model that must surely trend in one direction or the other however slightly.
In the event, we have a serious lack of proxies around the globe over a useful time range to provide confident projections. The historical weather data keeping that is most of two hundred years old has been vulnerable to the heat island effect adding yet another source of error that must be continuously adjusted with unaffected comparables. It has been claimed that this is well handled but even that has come into question.
We have data over a fairly short time period of two centuries in some parts of the globe. We have a lot more data covering the past century steadily improving to the beginning of satellite monitoring almost thirty years ago. Present methods can be the gold standard and actually accepted as having a very low measurable error. Yet that is only thirty years old and all preceding proxies, however obtained will always be suspect at least. Look at the debate over whether the warming of the 1930’s is comparable to the warming ending in 1998.
Right now we lack an explanation for the clear decadal heat shift from the south to the north. Or perhaps we mistake the cooling of the south as anomalous. It could well be simply a continuation of normal behavior that is perhaps slightly slowed because it is warmer generally. The cooling engine of the south is huge compared to the cooling effects of the northern winter. The idea that it is still cooling while a little more heat is keeping the north warmer could be made. Again we lack the centuries of data needed to address these facts coherently.
My principle hypothesis is that left to its own devices, the northern hemisphere will slowly warm to Bronze Age conditions in which the winter sea ice is fully removed every year. This implies improved growing conditions in the higher latitudes. The Baltic becomes pleasant again and the permafrost will disappear in Greenland and over vast swathes of the boreal forest. The tree line will perhaps advance a little.
The evidence shows that this natural warming trend of the atmosphere has been interrupted by volcanic activity again and again. It certainly appears to be the most likely causation of abrupt declines in temperatures over the span of the Holocene. Other sources of cooling will not be so obviously abrupt but still must be considered. The reason for this is that it appears that the earth conserves a lot more heat than we have ever given it credit for. The atmosphere is not the sole store of heat. Without doing a calculation, oceanic heat storage is easily as potent and the ambient temperature of land is also available very slowly.
We live in an ocean of heat and it is very difficult to determine trends and variances with any confidence let alone assign actual cause and effect.
1 The Northern Hemisphere has warmed. We know that because the Arctic has a longer spring and summer. A direct result has been the opening of the two northern sea routes for the first time. Also glaciers are retreating all over the northern hemisphere. That pretty well confirms that this is a warm spell. Even the number fools who note that 2008 is the coolest year in the past five point out that still means that it is above average and has been above average for five years. We need seriously below average now to reset the averages back to normal. So yes it is actually much warmer in the Arctic.
2 The Southern Hemisphere has cooled. Glaciers are growing. The amount of cooling involved is either a mirror image of the northern warming or a very large fraction thereof. It is colder and thankfully, we do not try to have billions live there.
3 External drivers such as excess CO2 and solar variation have been presumed to alter global temperatures. The scientific support for either proposition is tenuous. For CO2 it was for ten years clearly coincidental. Since then for ten years it has been contrary. The solar variation idea is also potentially coincidental but more compellingly so for the two specific cases that exist.
4 It is not obvious that Northern Europe is a viable proxy for the Globe. Again we have the present situation in which a clear northern warming trend is been countered by a southern cooling trend. This is an actual expectation for an invariable heat supply model that must surely trend in one direction or the other however slightly.
In the event, we have a serious lack of proxies around the globe over a useful time range to provide confident projections. The historical weather data keeping that is most of two hundred years old has been vulnerable to the heat island effect adding yet another source of error that must be continuously adjusted with unaffected comparables. It has been claimed that this is well handled but even that has come into question.
We have data over a fairly short time period of two centuries in some parts of the globe. We have a lot more data covering the past century steadily improving to the beginning of satellite monitoring almost thirty years ago. Present methods can be the gold standard and actually accepted as having a very low measurable error. Yet that is only thirty years old and all preceding proxies, however obtained will always be suspect at least. Look at the debate over whether the warming of the 1930’s is comparable to the warming ending in 1998.
Right now we lack an explanation for the clear decadal heat shift from the south to the north. Or perhaps we mistake the cooling of the south as anomalous. It could well be simply a continuation of normal behavior that is perhaps slightly slowed because it is warmer generally. The cooling engine of the south is huge compared to the cooling effects of the northern winter. The idea that it is still cooling while a little more heat is keeping the north warmer could be made. Again we lack the centuries of data needed to address these facts coherently.
My principle hypothesis is that left to its own devices, the northern hemisphere will slowly warm to Bronze Age conditions in which the winter sea ice is fully removed every year. This implies improved growing conditions in the higher latitudes. The Baltic becomes pleasant again and the permafrost will disappear in Greenland and over vast swathes of the boreal forest. The tree line will perhaps advance a little.
The evidence shows that this natural warming trend of the atmosphere has been interrupted by volcanic activity again and again. It certainly appears to be the most likely causation of abrupt declines in temperatures over the span of the Holocene. Other sources of cooling will not be so obviously abrupt but still must be considered. The reason for this is that it appears that the earth conserves a lot more heat than we have ever given it credit for. The atmosphere is not the sole store of heat. Without doing a calculation, oceanic heat storage is easily as potent and the ambient temperature of land is also available very slowly.
We live in an ocean of heat and it is very difficult to determine trends and variances with any confidence let alone assign actual cause and effect.