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Two degrees Celsius

The Road to the Eu’s +2oc Maximum Temperature Limit
Andrew Glikson
Earth and paleoclimate scientist
Australian National University

Taking into account the (1) masking effect of industry-emitted sulphur aerosols, and (2) lost reflectance (albedo) due to Arctic Sea ice melt and other parts of the polar and mountain glaciers, global temperature-equivalents are tracking close to the European Union maximum permissible level of 2 degrees Celsius.

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According to the IPCC AR4-2007 report [1] a total anthropogenic greenhouse factor of 3.06 Watt/m2, equivalent to about +2.3 degrees C, is masked by a compensating aerosol albedo effect of -1.25 Watt/m2 (mainly sulphur from industrial emissions) equivalent to about -0.9C (without land clearing albedo gain and ice melt albedo loss) (Table 1). Once the short-lived aerosols dissipate, adding the reflectance loss of melting polar ice (where maximum warming of up to 4 degrees C occurs; Figure 2), mean global temperatures track toward +2 degrees C, considered by the European Union to be the maximum permissible level.

From Table 1, subtracting the aerosol masking effect, the magnitude of the 1750 – 2005 mean forcing at ~3 Watt/m2 is approaching 50% of the total last glaciation termination of 6.5+/-1.5 Watt, not accounting for developments since 2005. This includes the reduction in albedo due to melting of Arctic Sea ice and other parts of the cryosphere.

Since the mid-1990s the mean global temperature trend has become increasingly irregular, representing an increase in climate variability with global warming, as reflected by variations in the ENSO cycle and oscillating ice melt and re-freeze cycles. The solar sunspot cycle effect is at about +/-0.1 degrees C, an order of magnitude less than greenhouse forcing. Sharp peaks include the 1998 El-Nino peak (near +0.55C) and the 2007 La Nina trough (near -0.7C) [2]. Mean global temperature continued to rise during 1999-2005 by about 0.2C (Figure 3).

The effects of this warming on the cryosphere include:

(A) Reduction in the Arctic Sea multi-year ice cover from about 4.2 to 2.5 million square km during 2000-2009 [3] (Figure 4).

(B) Increase in Greenland September ice melt area from 350,000 to 550,000 square km during 1997-2007 [4] (Figure 5).

(C) Warming of the entire Antarctic continent by 0.6C and of west Antarctic by 0.85C during 1957-2006 [5], reflected by collapse of west Antarctic ice shelves [6] (Figure 6).

Variations in temperature and sea ice cover around Antarctica are effected by the shrinking polar wind vortex and tropospheric and stratospheric ozone layer conditions, resulting in geographic and temporal variability in sea and land ice cover (Figure 7).

Ongoing global warming may lead to the release of methane from permafrost, collapse of the North Atlantic Thermohaline current, high-energy weather events and yet little-specified shifts in atmospheric states (tipping points) [7]

 

Table 1. Comparisons between anthropocene (1750-2005), last glacial termination (20 – 11.7 kyr) and Pliocene (~3 Ma) CO2 levels, climate forcings, mean global temperatures and sea levels. Sources: [1] and [19].

 

Period

CO2 ppm

Forcings

Watt/m2

Temperature oC

(1oC ~ ¾ W/m2)

Sea level

metres

1750 – 2005

260-387

Greenhouse: +3.06

Albedo: -1.25*

Current balance: +1.81

Ice albedo loss (? W/m2)

~ +2.3

~ -0.9

?ToC

Tracking toward Pliocene levels

Last glacial termination

(20 – 11.7 kyr

180-280

Greenhouse gases:

+3.0+/-0.5

Ice sheets and vegetation albedo loss: +3.5+/-1.0.

 

~ +5.0+/-1.0

+120

Pliocene

(3 Ma)

400

+2 to 3

+25 +/-12

*(not including land clearing)

 

This experiment by Homo “sapiens” is a novel one. Developments may include periods of cooling, as may be indicated by the current slow-down of Greenland glaciers. In a recent paper by Dakos et al. (2008) abrupt climate changes in the past are shown to have been preceded by quiet periods [8].

”Skeptics” use such short-term variability, for example slowing down of Greenland glaciers, to argue “global cooling” and thereby a “justification” for further carbon emissions [9 – 11].

The implications of climate change for ecosystems are illustrated in the new book Heatstroke: Nature in an Age of Global Warming by Anthony Barnosky, of Yale University, who states:

I think probably the biggest cause for worry is we really are seeing the disappearance of whole ecological niches, which means extinctions." [12]

Despite intensified warnings from the Copenhagen climate conference [13], as a self-fulfilling prophecy the government’s “great moral issue of our time” [14] is being relegated to secondary priority [15].

Given that warnings by scientists have proven mostly correct, as contrasted with watered-down reports percolating upward through bureaucracies, there is little evidence the Rudd government is listening to the recent dire warnings by climate scientists [16].

The decline by CSIRO to report directly to the recent Senate climate inquiry [17], reminiscent of the Howard era [18], has only been saved by the courage of individual scientists, one of whom compared Labor's targets to "Russian roulette with the climate system with most of the chambers loaded".

References

 

 

Figure 1.

IPCC 2007 Figure SPM.2. AR4-WG1-2007 - Global average radiative forcing (RF) estimates and ranges in 2005 for anthropogenic carbon dioxide (CO2 ), methane (CH4 ), nitrous oxide (N2O) and other important agents and mechanisms. The net anthropogenic radiative forcing and its range are also shown. Volcanic aerosols contribute an additional natural forcing but are not included in this figure due to their episodic nature.

 

 

Figure 2. NASA-GISS Land-Ocean temperature anomaly showing the strongest temperature anomalies occur over polar winters. (A) End of NH summer: September, 2008 relative to 1951-1980. Mean global anomaly 0.52oC. Note the high early-summer temperatures over Antarctica. (B) End NH winter: April 2009 relative to 1951-1980 baseline. Mean global anomaly: 0.43oC. Note the increase in temperatures over +4oC over eastern Siberia and a decrease by more than over -2oC over East Antarctica.

 

 

Figure 3. Mean global temperature changes (NASA/GISS).

1880 – 2009 annual mean and 5-year annual mean temperatures 1996 – 2009 monthly meteorological stations and Land-Ocean temperatures. index.

Note the 1998 El-Nino anomaly and 2008 La-Nina anomaly.

 

 

Figure 4. The decline in multiyear (including second-year ice) sea ice coverage measured by NASA’s QuikScat satellite from 1999 to 2009. Each field shows the coverage on January 1 of that year. There is a 40 percent drop in coverage between 2005 and 2007.

 

 

Figure 5. Change in the extent of Greenland ice melt areas from 350,000 km2 in September 1997 to 550,000 km2 in September 2007

 

 

Figure 6. The Antarctic continent (upper image) and temperature changes per decade during 1958 – 2008 (lower image). Note the contrast between west and east Antarctica and the internal variations of warming and slightly cooling regions in east Antarctica.

 

 

Figure 7 (A) Antarctic sea ice extent during SH Winter (September, 1999) and summer (February, 2009). (B) Sea ice per cent concentration trends around Antarctica for October 2008 relative to 1979-2000 October monthly average. National Snow and Ice Data Centre.

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How do people fall for this stuff?

Climate change is already responsible for 300,000 deaths a year and is affecting 300m people, according to the first comprehensive study of the human impact of global warming.

Nobody denies climate change - no rational person ever has. To deny climatic changes is to deny winter and summer. Sensible (and non-scammers) people simply deny human beings have control over climate conditions.

People have always died from extreme weather changes. With the advancement of civilization, I'd be surprised if this number hasn't been reduced when compared to the past figures (accounting for population increases). Which of course the UN storytellers didn't supply, or they were just too busy panhandling for 40 billion.

It projects that increasingly severe heatwaves, floods, storms and forest fires will be responsible for as many as 500,000 deaths a year by 2030, making it the greatest humanitarian challenge the world faces.

With increases in population, I'd be hugely surprised if natural disasters didn't kill this many (unadjusted figures). I wonder how long it took the "thinktank" to do this basic mathematics?

Andrew Glikson: "Significantly some of the most prominent pro-carbon advocates in the US have acted in the past as promoters of tobacco companies ... "

Ohhhh, how sinister.

The argument going well is it?

Now the real thing that will do the real damage in real life is rampant inflation. The beast that every government is so desperately trying to unleash. Well, I think soon their wish is going to be realised.

Now that, ladies and gentlemen, is when one will really see some third world action. And not the nice climate change kind.

Global warming already causes 300,000 deaths per year

Well, Pat, since we're quoting things we read on the Internet, here's today's latest addition

Climate change is already responsible for 300,000 deaths a year and is affecting 300m people, according to the first comprehensive study of the human impact of global warming.

It projects that increasingly severe heatwaves, floods, storms and forest fires will be responsible for as many as 500,000 deaths a year by 2030, making it the greatest humanitarian challenge the world faces.

Economic losses due to climate change today amount to more than $125bn a year — more than all the present world aid. The report comes from former UN secretary general Kofi Annan's thinktank, the Global Humanitarian Forum. By 2030, the report says, climate change could cost $600bn a year. 

Also, I read on the internet that we all ought to be preparing to defend the planet against an alien invasion - which is way more believable than your global cooling site.

Climate

David, thanks for your comments.

I envy those who are able to deny the reality of dangerous climate change.  It is a thankless task to attempt to warn people that continuing to use the atmosphere as an open channel for carbon gases is bound to have similar effects on the biosphere as smoking has on the lungs.  Significantly some of the most prominent pro-carbon advocates in the US have acted in the past as promoters of tobacco companies ...

Climate warming

I believe in climate change: the world is cooling since 1998. I read it on the internet. So it is more likely to be true than the stories on warming in the Australian...

Solar activity is the key. Most of the energy of the sun is not visible and is quite variable.

Want to learn more?

http://www.etheric.com/LaViolette/Predict.html

only vaguely on warming but why should I argue with you about your beliefs. They are yours and I have mine. I believe that 99% of all liars who ever lived are now alive and in the IPCC and governments around the world...

If I am right, the world will start to record failing crops from rain and cold. Tell you what, why not revisit this topic every month for the next 25 years? Every month. I wonder what Marilyn thinks?

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