Posts Tagged ‘Surface temperature’

John Christy on Summer Heat and James Hansen’s PNAS Study

Monday, August 20th, 2012

Source:  Global Warming Org

Dr. John Christy

In a recent study published in Procedings of the National Academy of Sciences (PNAS), NASA scientist James Hansen and two colleagues find that whereas “extremely hot” summer weather ”practically did not exist” during 1951-1980, such weather affected between 4% and 13% of the Northern Hemisphere land area during 2006-2011. The researchers infer that human-caused global warming is “loading” the “climate dice” towards extreme heat anomalies. They conclude with a “high degree of confidence” that the 2003 European heat wave, the 2010 Russian heat wave, and the 2011 Texas-Oklahoma drought were a “consequence of global warming” and have (as Hansen put it in a recent op-ed) ”virtually no explanation other than climate change.”

In a recent post, I reviewed studies finding that the aforementioned anomalies were chiefly due to natural variability. In another post, I summarized an analysis by Patrick Michaels and Chip Knappenberger, who conclude that “the 2012 drought conditions, and every other [U.S.] drought that has come before, is the result of natural processes, not human greenhouse gas emissions.” (more…)

Tree-rings prove climate was WARMER in Roman and Medieval times

Wednesday, July 11th, 2012

Source:  UK Mail

  • Tree ring study gives first accurate climate reading back to 138BC
  • World has been slowly cooling for 2,000 years
  • World was warmer in Roman and Medieval times than it is now
  • Study of semi-fossilised trees in Finland
Rings in fossilised pine trees have proven that the world was much warmer than previously thought – and the earth has been slowly COOLING for 2,000 years.

Measurements stretching back to 138BC prove that the Earth is slowly cooling due to changes in the distance between the Earth and the sun.

The finding may force scientists to rethink current theories of the impact of global warming.

It is the first time that researchers have been able to accurately measure trends in global temperature over the last two millennia. (more…)

One hundred years of global temperature change

Wednesday, April 4th, 2012
Source:  Climate Change Reconsidered
Reference
Ludecke, H.-J., Link, R. and Ewert, F.-K. 2011. How natural is the recent centennial warming? An analysis of 2249 surface temperature records. International Journal of Modern Physics C 22: 10.1142/S0129183111016798.

Working with 2249 globally-distributed monthly temperature records covering the period 1906-2005, which they obtained from NASA’s Goddard Institute for Space Studies, Ludecke et al. (2011) evaluated “to what extent the temperature rise in the past 100 years was a trend or a natural fluctuation.” (more…)

Two new papers on surface temperatures

Thursday, November 3rd, 2011

Source:  Bishop Hill

Nov 3, 2011

Horst-Joachim Lüdecke (who is involved with EIKE, the German sceptic group) emails about two new papers he has on surface temperatures. He tells me that these contradict BEST.

The first is in the International Journal of Modern Physics and is entitled “How Natural is the Recent Centennial Warming? An Analysis of 2249 Surface Temperature Records“.

Abstract. We evaluate to what extent the temperature rise in the past 100 years was a trend or a natural fluctuation and analyze 2249 worldwide monthly temperature records from GISS (NASA) with the 100-year period covering 1906-2005 and the two 50-year periods from 1906 to 1955 and 1956 to 2005. No global records are applied. The data document a strong urban heat island eff ect (UHI) and a warming with  increasing station elevation. For the period 1906-2005, we evaluate a global warming of 0.58°C as the mean for all records. This decreases to 0.41°C if restricted to stations with a population of less than 1000 and below 800 meter above sea level. About a quarter of all the records for the 100-year period show a fall in temperatures. Our hypothesis for the analysis is – as generally in the papers concerned with long-term persistence of temperature records – that the observed temperature records are a combination of long-term correlated records with an additional trend, which is caused for instance by anthropogenic CO2, the UHI or other forcings. We apply the detrended  fluctuation analysis (DFA) and evaluate Hurst exponents between 0.6 and 0.65 for the majority of stations, which is in excellent agreement with the literature and use a method only recently published, which is based on DFA, synthetic records and Monte Carlo simulation. As a result, the probabilities that the observed temperature series are natural have values roughly between 40% and 90%, depending on the stations characteristics and the periods considered. ‘Natural’ means that we do not have within a defi ned con fidence interval a defi nitely positive anthropogenic contribution and, therefore, only a marginal anthropogenic contribution can not be excluded. (more…)

Rear Mirror – Climate uncertainties

Wednesday, September 8th, 2010

by Dennis Ambler

Remember that the science was settled even back in 1997, at Kyoto? Well, it seems it wasn’t that settled two years later and the current models (state of the art!)  are just complex, unauditable aggregations of the models used then, such as MAGICC. We are now up to MAGICC 6.

Representing Uncertainty in Climate Change Scenarios and Impact Studies

ECLAT-2 Workshop Report No . 1 Helsinki, Finland, 14-16 April 1999

Edited by : Timothy R. Carter , Mike Hulme and David Viner

Published by the Climatic Research Unit, UEA, Norwich, UK. September 1999

Uncertainty in Representing Observed Climate

Mark New, Climatic Research Unit, School of Environmental Sciences, University of East Anglia, Norwich,

Surface climate measurements are subject to a range of influences that can lead to random data errors, biases and inhomogeneities. (more…)

NOAA, CONGRESS, USHCNV2 and an Expensive New Climate Network

Tuesday, August 10th, 2010

Source: http://icecap.us/index.php/go/joes-blog

By Joseph D’Aleo

The Inspector General wrote on behalf of NOAA a response to Congressman Barton and Rohrabacher and the other committee members about the issues raised about the US climate data base (USHCN) (see attached letter and report here). They spoke with the NWS, NCDC, ATDD, several state climatologists, the AASC, the USGRP and the AMS to form their response. They examined quality control procedures, background documentation, operating procedures, budget requirements and management plans. (more…)

More Temperature Data Concerns

Friday, December 18th, 2009
Posted by Joe D’Aleo
China - NOAA GHCN
The NOAA GHCN data for China shows a temperature that was in part responsive to large changes in the network of observing sites. E.M. Smith noted a major dropout starting shortly before 1990 after the global warming effort took flight (Hansen’s testimony was in the summer of 1988).
The station distribution became increasingly urban, more tropical, more lower elevation, all of which would cause/enhance the shown warming. Current station numbers remain lower than anytime back to 1930. The stations were not closed. They can still be found on the web reporting hourly data.

The Russian IEA found a similar station situation with a station dropout from 476 to 121. The new subset had 0.64C more warming and were biased towards stations with partial data (opportunity for mischief) and urbanized.

Climate science Q&A: warmest decade on record?

Saturday, December 12th, 2009

By Christopher Monckton of Brenchley

We are happy to answer this query from a reader about recent global temperature trends.

Dear Lord Monckton, – The UK Meteorological Office has just issued a statement that the past decade has been the warmest on the instrumental record. Is this true?

Dear Enquirer, - Yes, it is true - assuming that we can any longer believe the surface global temperature record, which we now know to have been so widely tampered with by the compilers of all of the major terrestrial-temperature datasets that, in particular, we do not really know whether the 1930s were warmer than the 2000s worldwide: they certainly were in the US.

It is also worth pointing out that for nine full years, since the turn of the millennium on 1 January 2001, there has been rapid and statistically-significant global cooling. This cooling follows a very sharp upward step-change in global temperatures between 1997 and 2000, which may have something to do with the Great El Nino of 1998, the first in the instrumental-temperature era. Of this cooling, one of the key players in the Climategate email scandal had this to say -

 

The fact is that we can’t account for the lack of warming at the moment and it is a travesty that we can’t. The CERES data published in the August 2009 Bulletin of the American Meteorological Society supplement on 2008 shows there should be even more warming: but the data are surely wrong. Our observing system is inadequate.”

 

So the conspirators are privately admitting we’ve been right all along about global cooling, and that it’s a travesty they can’t explain it, while publicly proclaiming that this decade’s temperatures are the warmest in 150 years and that this is because of “global warming”.

 

Finally, I recently sat at the feet of Professor Fred Singer, to whose attention I had drawn an interesting paper by Lindzen and Choi (2009), demonstrating that the radiation escaping from the Earth to space, as measured by the Earth Radiation Budget Experiment (ERBE) Satellite, is not being trapped in the Earth’s atmosphere to cause warming down here, to anything like the extent that the models predict.

 

The Professor looked very closely at the diagram showing the anomalies in short-wave and, separately, in long-wave radiation, and noticed that, though both had run level until 1997 (and, indeed, there had been no “global warming” from 1980 to 1997), they had been sharply dislocated until 2000, when short-wave radiation ran level at a new and lesser flux, while long-wave radiation ran level at a new and greater flux.

 

The significance of the Professor’s sharp-eyued observations is this. First, the sudden step-change upward in global temperature between 1997 and 2000 is the only warming since the satellite record began in 1980. Before it, there was no warming: after it, there was rapid cooling. It is important to understand that this non-uniform pattern of warming is entirely inconsistent with the steadily-increasing radiative-forcing effect of CO2 concentrations increasing at 2 ppmv/year over the past decade, and cannot, therefore, have been caused by it, for lack of correlation necessarily implies lack of causation.

 

Secondly, the diminished short-wave radiation after 2000 indicates a reduction in cloud cover, for the clouds reflect short-wave radiation harmlessly back to space. The reduction in cloud cover (whose cause is not clear, for we know exasperatingly little about cloud formation, and this on its own introduces an uncertainty into all climate calculations that renders the claim that “the science is settled” laughable) allows more of the visible and hence high-energy solar radiation to reach the Earth’s surface, where it is displaced to the long-wave and can then interact with greenhouse gases on its way out. This sudden increase in long-wave radiation, attributable to the sudden loss of cloud cover indicated by the loss of short-wave radiation reaching the satellite, is quite enough to explain why temperatures have been higher since 2000 than before.

 

The bottom line: careful attention to the observational data provides explanations for the pattern of temperature change that are much less incomplete and more satisfying than CO2, CO2, CO2. The Professor and I differ on the extent to which phenomena such as changes in cloud cover are deterministic: he looks for a climate in which all influences are eventually explained and understood as causative sequences, while I go with Edward Lorenz (1963), who said that because the climate is mathematically chaotic the reliable long-term prediction of what will happen next in the climate is unobtainable by any method.

 

However, the Professor and I are at one that the warming of the past 300 years, during 280 of which we could not have been in any way responsible, is all or very nearly all natural. Both of us will be doing more work on why there was a step-change upward in temperature from 1997-2000; but, even on the UN’s exaggerated estimate of CO2′s warming effect, CO2 cannot – repeat cannot – have been to blame.

If the Climategate conspirators had been less politicized and less dishonest, they would have been having conversations of this kind, rather than working out ways of bending the data so as to blame more than half of the warming from 1975-1998 on CO2. – Monckton of Brenchley