Monday, January 22, 2007


From "Meteorology and Atmospheric Physics" 95, 115-121 (2007)

Multi-scale analysis of global temperature changes and trend of a drop in temperature in the next 20 years


A novel multi-timescale analysis method, Empirical Mode Decomposition (EMD), is used to diagnose the variation of the annual mean temperature data of the global, Northern Hemisphere (NH) and China from 1881 to 2002. The results show that: (1) Temperature can be completely decomposed into four timescales quasi-periodic oscillations including an ENSO-like mode, a 6-8-year signal, a 20-year signal and a 60-year signal, as well as a trend. With each contributing ration of the quasi-periodicity discussed, the trend and the 60-year timescale oscillation of temperature variation are the most prominent. (2) It has been noticed that whether on century-scale or 60-year scales, the global temperature tends to descend in the coming 20 years. (3) On quasi 60-year timescale, temperature abrupt changes in China precede those in the global and NH, which provides a denotation for global climate changes. Signs also show a drop in temperature in China on century scale in the next 20 years. (4) The dominant contribution of CO2 concentration to global temperature variation is the trend. However, its influence weight on global temperature variation accounts for no more than 40.19%, smaller than those of the natural climate changes on the rest four timescales. Despite the increasing trend in atmospheric CO2 concentration, the patterns of 20-year and 60-year oscillation of global temperature are all in falling. Therefore, if CO2 concentration remains constant at present, the CO2 greenhouse effect will be deficient in counterchecking the natural cooling of global climate in the following 20 years. Even though the CO2 greenhouse effect on global climate change is unsuspicious, it could have been excessively exaggerated. It is high time to re-consider the trend of global climate changes.

1. Introduction

On interdecadal timescales, whether the global temperature will continue to warm up or to drop in the coming 20 years is not only a hot spot but also a daunting task in global climate change research as shown in many studies (Stott and Ketteborough, 2002; Schneider and Held, 2001; Michael and Jeffrey, 1995). In recent decades, scientists have paid more attention to the CO2 greenhouse effects on global climate changes. Some modeling studies (Caldeira and Duffy, 2000; Sarmiento et al, 1998; Manabe and Stouffer, 1993) indicated a relatively significant Southern Ocean sink due to anthropogenic CO2. Many researches (Houghton et al, 2001; Joos et al, 1999; Sarmiento and Quere, 1996; Manabe and Stouffer, 1994) argued that when CO2 doubled in the atmosphere, the global mean temperature would increase by about 1.4 to 5.8 C. That means the global mean temperature will rise as a result of the increase of CO2 in the atmosphere. But Petit et al (1999) and Stauffer et al (1998) thought that the increasing greenhouse effects would only partly induce the global to warm up as a natural variation process. And the past records have indicated that the increase of CO2 concentration did not occur before the warming up as shown by some studies (Fischer et al, 1999; Schlesinger and Ramankutty, 1994).

Since it is now obvious that the CO2 content in the atmosphere does not decrease, will the global temperature go on warming up in the following decades like that in the 20th century? Global climate change is affected not only by anthropogenic activities (the increase of CO2 concentration in the atmosphere), but also through natural factors in climatic system (driving forces) such as solar activities. The natural driving forces and combined forces generally display multitimescale oscillations. Thereby, to answer this question, it is primary to ravel whether the climatic period (quasi-period) variation on different timescales or the natural variation trend is affected by the variety of CO2 concentration in the atmosphere, or which climatic quasi period is most affected by the increase of CO2 concentration in the atmosphere.

Fourier analysis is used as a general tool for examining time series. Although it is valid under general conditions, there are some crucial restrictions of Fourier analysis, i.e., the system must be linear and the data must be periodic or stationary. However, climate dataset is both nonlinear and non-stationary with multi-timescale oscillations. By applying the traditional timeseries techniques based on Fourier Transforms, one can get a time-frequency distribution through sliding the window successively along the time axis. Meanwhile, it has to assume the data to be strictly stationary. Furthermore, the window width must be narrow, and the frequency resolution requires longer time series. The wavelet approach is essentially an adjustable window Fourier spectral analysis, and it is of non-adaptive nature. Once the basic wavelet is selected, one will have to use it to analyze all the data. SSA is the Fourier transform of the empirical orthogonal function (EOF), so we have to ensure that each EOF component is stationary. Otherwise, the Fourier spectral analysis will make little sense as for the EOF components. Unfortunately, we cannot guarantee that EOF components derived from a nonlinear and nonstationary dataset are both linear and stationary.

Hereby, in order to overcome the difficulty of studying nonlinear and non-stationary time series, a method called the Empirical Mode Decomposition (EMD) was developed in 1998 by Huang et al (1998; 1999) to facilitate the decomposition of climate records in terms of natural oscillatory patterns and trends. We try to use this method to analyze the maximum weight of CO2 greenhouse effect on global temperature variation on multi-scales. Based on it, it is possible for us to forecast whether global climate will continue to warm up or to cool down in the next 20 years.


6. Discussion

EMD method can decompose climate dataset into various timescale oscillations and each IMF component indicates temperature variation on different timescales. The trend and the quasi-60-year oscillation are the most prominent in temperature variation in the global, NH and China. In the meantime, temperature variation in China precedes that in the global and NH, so it provides a denotation for global climate changes. Noticeably, the interdecadal oscillations of temperature in China which was at its peak in 2001 have been falling recently. It thus indicates that whether on century scale or on the periods of quasi 60-year oscillations, the global climate will be cooling down in the next 20 years. It should be noted that we did not forecast it on the timescale of month or year. On the month or year timescale, the influencing factors in climate change are both numerous and inconstant. Therefore, climate change is of multi-frequencies or frequency conversion. But on 60-year to century timescale, the influencing factors in climate change are relatively stable. So, we consider global temperature will be in falling on 60-year timescale in the coming 20 years. And again, our primary conclusion, i.e., that atmospheric CO2 concentration is not a key determinant of periodic variation of the global temperature. The global climate warming is not solely affected by the CO2 greenhouse effect. The best example is temperature obviously cooling however atmospheric CO2 concentration is ascending from 1940s to 1970s. Although the CO2 greenhouse effect on global climate changes is unsuspicious, it could have been excessively exaggerated. It is high time to re-consider the global climate changes. We consider that CO2 greenhouse effect impact on the trend of global temperature, simultaneity we expect to find the effect on climate change on different timescales by analysis the solar activity, earth movement (nutation, rift and volcano activity) and the others greenhouse gases using EMD method.


The cost of combating climate change could be 40 per cent lower than the figure given in last year's watershed Stern report on the economic impact of global warming, according to research to be announced today. The research will be presented by Lars Josefsson, chief executive of Vattenfall, the Swedish power company, and is likely to attract particular attention as he is a special adviser on the environment to Angela Merkel, Germany's chancellor.

Germany took on the presidency of the European Union on January 1 and Ms Merkel has made combating climate change a centrepiece of its rule. Sigmar Gabriel, Germany's environment minister, will attend the talk by Mr Josefsson. "The cost of limiting the concentration of greenhouse gases is equivalent to 0.6 per cent of the total gross world product - if all the identified potential is exploited," Mr Josefsson told the FT.

Sir Nicholas Stern, a UK economist, propelled climate change up the political agenda in a report that claimed global warming could shrink the world economy by 20 per cent if nothing was done, but that action today would cost 1 per cent of GDP.

Mr Josefsson's report says lower costs can be achieved using measures that "pay for themselves", such as insulation improvements and fuel efficient cars. But it also envisages more use of nuclear power and carbon capture technology.

The research, which was paid for by Vattenfall, forms part of a drive by Mr Josefsson to enhance the role played by the world's leading companies to combat climate change. He oversaw last week's announcement of the creation of the 3C initiative, in which 15 of the world's largest companies joined forces to devise "commercial solutions and market-based investments" to climate issues.

US companies such as General Electric, NRG Energy and Duke Energy signed up to the 3C initiative, a development Mr Josefsson said meant the interests of US business and climate protection were becoming increasingly aligned. He hopes the revelation that tackling global warming could be much cheaper than first thought, and led by large businesses, will galvanise political leaders into addressing climate-related issues. Mr Josefsson plans to present the research to business leaders in Davos this month and will travel to Asia to convince business leaders there to join the 3C programme.



GUESTS at a 300 pound-a-head climate change conference turned up in a stream of gasguzzling sports cars and 4x4s. Former US vice president Al Gore was the main speaker at yesterday's event in the Hilton Hotel in Glasgow. While the meeting was to address global warming, business leaders turned up in a range of flash motors including Bentleys, Jeeps and Porsches. One onlooker said: "This was for a conference on how to save the planet. It would appear the irony was lost on them." ......

More here


Showing that warming could not be the cause of extreme weather. Summary from "ArXivPhysics" November 2006

We theoretically study the statistics of record-breaking daily temperatures and validate these predictions using both Monte Carlo simulations and 126 years of available data from the city of Philadelphia. Using extreme statistics, we derive the number and the magnitude of record temperature events, based on the observed Gaussian daily temperature distribution in Philadelphia, as a function of the number of years of observation. We then consider the case of global warming, where the mean temperature systematically increases with time. Over the 126-year time range of observations, we argue that the current warming rate is insufficient to measurably influence the frequency of record temperature events, a conclusion that is supported by numerical simulations and by the Philadelphia data. We also study the role of correlations between temperatures on successive days and find that they do not affect the frequency or magnitude of record temperature events.


In meteorology, as in real estate, it seems location is everything -- making generalizations very shaky

Nine years after the National Weather Service moved its official weather station from downtown Los Angeles, a team of researchers has found that the station's new home, though only four miles away, experiences significantly different weather. "If you move it, you make it cooler and drier," said Bill Patzert, a Jet Propulsion Laboratory climatologist and one of the study's researchers. "You're fooling with Mother Nature's climate record."

After spending many years atop a Department of Water and Power parking garage, the official station is now located at ground level on the University of Southern California's lush campus. Because it's closer to the ocean and at lower elevation, Patzert and his colleagues found, the official weather of Los Angeles is now about 2 degrees Fahrenheit cooler than it would be otherwise. "As far as making a weather forecast prediction, it's not really a problem for us," said National Weather Service Meteorologist Eric Boldt.

But for climatologists seeking to measure the effect of global warming and urban heat islands, every degree is significant. Scientists believe global warming increased the Earth's overall temperature 1.1 degrees Fahrenheit during the last century.

Los Angeles' record is likely not the only one affected by station relocations. Around the country, many official National Weather Service observation posts have been moved as the government shifted to automated systems. "When I presented this paper in San Antonio [at the annual meeting of the American Meteorological Society this week], the response was overwhelming - everyone had a story to tell about how stations had been moved," Patzert said. "It's not local, it's not isolated, it's not unique."

Before the move, the official weather had been recorded from downtown Los Angeles since 1877, though even in those times there were debates about the merits of different locations. An 1892 Los Angeles Times article noted of the official record, collected at that time by the Signal Service: "While the Government's [rain gauge] is located at the top of a four-story building the others are placed on or near the surface of the ground." The difference, they wrote, "represents a uniform and almost unvarying tendency of the Signal Service to underestimate our rainfall."

After its most recent move, Patzert found, the station now records an inch less rain each year, on average. This had some disappointing side-effects for Patzert. "[The winter of] 2004-2005 set a new record, it was the wettest year on record - but you have to use the Department of Water and Power data," he said. "They cheated all of us weather nuts out of our record." Instead, he'd like for the National Weather Service to move its official Los Angeles site back to the previous location, where weather conditions are still recorded daily. But according to meteorologist Boldt, "there's no prospect of that."



Many people would like to be kind to others so Leftists exploit that with their nonsense about equality. Most people want a clean, green environment so Greenies exploit that by inventing all sorts of far-fetched threats to the environment. But for both, the real motive is generally to promote themselves as wiser and better than everyone else, truth regardless.

Global warming has taken the place of Communism as an absurdity that "liberals" will defend to the death regardless of the evidence showing its folly. Evidence never has mattered to real Leftists

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1 comment:

Anonymous said...

Of course, the Chinese do have their share of global-warming hysterics, as well...

They've even done away with all the data that lead up to the curve at the end of the 'hockey stick,' and just looked at the increase from 1951
then they project the last 50 years into the future. They also have some 'supporting material.'