inconvenant truth = "Medieval Warm Period"?

Answer 1

I assume you are wondering if global warming is the same as the Medieval Warm Period (MWP) extending from about the 10th to the 14th century and then was itself followed by the "Little Ice Age" (LIA) extending from the 14th century to the mid 19th century.

The answer is no. If you follow the first link below there is a very nice graph of several different reconstructions of historic temperatures. Looking just at the graph itself and ignoring causes for a moment you can see quite clearly that the warming trend of the last 100 years is very considerably sharper than the warming trend preceding the MWP. That warming trend extended over about 400 years appearing to start around 600 AD over which period temperatures increased between 0.20 and 0.40 degrees. That is a heating rate of between 0.05 and 0.10 degrees per century.

In the global warming period (GWP) from about 1900 to present the temperature change as been about 0.80 degrees over a period of just one century. That is a rate of change that is between 8 and 16 times faster than the lead up to the MWP. That difference in rate of change is very strong evidence that the mechanisms and final outcomes will be much different.

Further again looking at the data, we can see that the MWP peak average was about 0.40 degrees less than temperatures that we are seeing today. Again that is substantial and indicative of a significant difference between the two phenomenon. So looking solely at the data trends I think a strong case can be made that the the two are not equivalent.

There is even stronger evidence that the MWP is not the same a GW because the MWP appears not to have been a global event but rather a localized phenomenon centered around the North Atlantic and Europe. Central Antarctica for example experienced a period of cooling during the MWP. The same is not the case for the GWP where substantial heating is occurring globally with only very isolated areas experiencing cooling (see the third link).

Looking at mechanisms it is thought that the MWP is correlated with a period of increased solar activity named the Medieval Maximum, although the correlation is not perfect in that MWP appears to peak 100 to 200 years earlier than does the period of solar activity. The implication is that MWP is due perhaps in part to increased solar activity but also some other forcing agent as well was active.

Within the period of GW there is less evidence of solar forcing. Although solar activity is relatively high, solar forcing and volcanic activity are relatively minor players compared to the very large CO2 changes. CO2 forcing is estimated to be responsible for about 85% of the temperature change.

Answer 2

Yes its true there was a "medieval warm period", but the current levels today are much higher than that period. PLUS, the major arguement is not over the existence of global warming. But rather whether or not its caused by humans.

Personally, I say no. Humans are not the cause. But I do believe we do contribute.

Answer 3

Regardless it is a truth, rumour, theory, myth or Al Gore....the Earth is experiencing greater than ever high in tempreture!
People can call it propaganda etc but see yourself datas, independent Reports, satellite pictures, records, scientists and Houston!
The sky isnt falling sure!!! but how come ice is melting in the Artic greater than before ,more than ever in June and Houston is experiencing and been labelled as the most polluted city in the world!
Sometimes it is better to set political ideology aside from the reality and science!!! Global warming is about humans ignoring mother nature and pretend they have right to pollute and pocketed profits and wealth.

Answer 4

I must agree that we had a little warming at the time these posts were made (9 yrs. ago), but the trend did not hold. It is cooler (the world) than it was when these posts were made, and despite what Odumberthansalt says, Ice is growing, not shrinking, if you measure the whole year and not just SUMMER action, as he just recently did. Global ie climate change is just another financial gizmo. FOLLOW THE MONEY.

Answer 5

If you're referring to Al Gore's witless propaganda flick, note that the Earth's temperature has been changing since the time it formed. Remember the Ice Ages? As for the notion that humankind is responsible for global warming, let me assure you that the sky is not falling.

Answer 6

there was a very cold period 1600-1800 now is part of a change to normal.

note there was ice in washington dc
rivers if U.K. frozen over..

Answer 7

I'm not sure what you're asking. Could you rephrase?