Klimaet cykler på vulkaner
Daily Mail skriver at undersøiske vulkaner ifølge et nyt studie påvirker klimaet mere end ellers antaget.
Volcanoes lurking hidden under the world’s oceans may play a far greater role in climate change than previously thought, according to a new study.
Scientists have found that underwater volcanoes, which were long assumed to ooze lava at relatively steady rates, in fact erupt in pulses.
A new study has shown that these submarine eruptions follow regular cycles that can range from just a couple of weeks to 100,000 years.
Surprisingly the researchers also found that these eruptions also appear to be clustered during the first six months of each year.
The findings may now mean that models predicting how human activity will change the climate will need to be adjusted.
Volcanic eruptions are known to throw huge amounts of gas into the atmosphere, including carbon dioxide that are thought to increase global warming.
However, volcanoes also release aerosol gases that are now known to reduce global warming by creating a reflective barrier against the sun.
Dr Maya Tolstoy, a marine geophysicist at the Lamond-Doherty Earth Observatory at Columbia University, said: ‘People have ignored seafloor volcanoes on the idea that their influence is small, but that’s because they are assumed to be in a steady state, which they’re not.
‘They respond to both very large forces, and to very small ones, and that tells us that we need to look at them much more closely.’
Watts Up With That har mere om den videnskabelige del. No Tricks Zone referer til et andet og tysk studie, der mener at vise at klimaet ligger under for ganske mange cyklusser, hvilket måske gør det muligt at spå lidt om fremtidens klima (og heri ligger intet om mennesket ændrer på præmisserne gennem afbrænding af fossile brændstoffer)
In principle these cycles are sinusoidal in behavior as depicted in Figure 1. Bob Tisdale has also shown how the temperature increase of the 65-year cycle from 1975 to 1998 led to the assumption that it is due CO2 emissions because they too happened to be parallel. This has been naively extended all the way to the year 2100 and forms the basis for the climate models and the invention of the so-called “climate catastrophe”.
Figure 1: Sine wave characteristic of the 60/65-year ocean cycle (Source: Bob Tisdale at WUWT).
In this analysis we will attempt to see how the temperature development could be over the next 700 years, assuming of course that the mentioned climate cycles of the past will continue on into the future. This should not be (mis)understood as a forecast for the future climate. Up to now there is only the IPCC forecast that the global temperature will rise by 2 to 5°C by the year 2100 – based only on the expected CO2 increase. However that theory has failed to work over the last 18 ears because the various natural climate factors and cycles never got considered, or they were not allowed to be considered in the climate models. Included among these factors are the mean cloud cover (albedo) and the resulting effective solar insolation (watts per sqm) at the earth’s surface, or the sea surface, which is decisive for the temperature development.Next Figure 2 below depicts the 1000-year cycle and the 230-year cycle, which have been reconstructed from historical proxy data. They stem from a combination of results from various publications in the field of paleoclimatology over the last years. The diagram of the last 3200 years distinctly shows a 1000-year cycle; the last 2000 years of which are confirmed by historical documents. In fact this cycle goes back all the way to the end of the last ice age, i.e. some 9000 years. The reason for the cycle is still unknown today, yet its existence is undisputed.
The current warm period is no “anthropogenic product”, rather it is the natural result of a repeating 1000-year cycle that goes back far into the past. Today’s warm period does not even reach the temperatures seen in the past warm periods, which at times were 1 to 2°C higher. Moreover it is important to note that during both of the past temperature maxima of 1000 and 2000 years ago, the CO2 values were at 280 ppm while today they are at 400 ppm. This indicates that the earlier warmer periods likely were related to natural solar activity and not to a rise in CO2 because there was no CO2 rise during those warm phases.
Figure 2: Global temperature over the last 3200 years shows a distinct 1000-year cycle along with the 230-year cycle.
Of historical significance is the fact that over the course of human history warm periods were always times of economic and cultural prosperity. The cooler periods always led to serious problems that led to starvation and huge waves of human migration in Europe. Here it becomes undeniably clear that the alarmist claims that “the earth has a fever” made by politicians such as Al Gore are patentedly preposterous.
- See more at: http://notrickszone.com/2015/02/02/german-analysis-current-warm-period-is-no-anthropogenic-product-major-natural-cycles-show-no-signs-of-warming/#sthash.VkC0WQJT.BRFPqPLu.dpuf
Men hvad forstår bønder sig på agurkesalat?
0 Kommentarer »
Ingen kommentarer endnu.
RSS feed for comments on this post. TrackBack URI