Greenland melting faster

GREENLAND'S ice sheet is more sensitive to global warming than previously thought, according to Spanish and German researchers.

The ice sheet may lose its ability to grow once warming reaches 1.6 degrees, a study published in Nature Climate Change found.

That is below the previous best estimate of 3.1 degrees, scientists at Madrid's Complutense University and Germany's Potsdam Institute for Climate Impact Research found. ''We might already be approaching the critical threshold,'' said Alexander Robinson, the lead author and an academic affiliated with both institutions.
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''The more we exceed the threshold, the faster it melts.''

The United Nations estimates Greenland's ice sheet holds enough water to raise global sea levels by seven metres, threatening coastal cities.

http://www.theage.com.au/world/greenland-melting-faster-20120312-1uwbk.html



Now tell me this: Does white relfect the sun's heat? If so,will less ice mean even higher tempratures (eg. less white stuff to repel the suns heat).

Anyone know anything about physics and colours and heat reflection?

It's called the albedo effect. This is the amount of electromagnetic radiation that reflects away, compared to the amount that gets absorbed. A perfectly reflective surface would get an albedo score of 1, while a completely dark object would have an albedo of 0. Ice has an albedo close to 1 while oceans are close to 0. 

It's called the albedo effect. This is the amount of electromagnetic radiation that reflects away, compared to the amount that gets absorbed. A perfectly reflective surface would get an albedo score of 1, while a completely dark object would have an albedo of 0. Ice may reflect up to 90 percent of incoming solar radiation (albedo = 0.9), while ocean water may absorb up to 90 percent (albedo = 0.1).

As we lose ice we lose albedo and the thermostat goes up. It's one of those positive feedback effects that has the climate scientists concerned.


red baron wrote on Mar 13^th, 2012 at 8:51am:


Either you are incredibly gullible, red baron, or you are willfully and malevolently spreading false information. The UK High Court judge, Justice Burton, actually rejected the lawsuit by political activist Stuart Dimmock to stop the distribution of Al Gore's An Inconvenient Truth to British schools. Justice Burton agreed that

"Al Gore's presentation of the causes and likely effects of climate change in the film was broadly accurate."

There were nine points where Burton decided that AIT differed from the IPCC and that this should be addressed in the Guidance Notes for teachers to be sent out with the movie.

Al Gore is not a scientist, he is an environmentalist who does a pretty good job informing the public about the science behind AGW. If Gore makes an "error" in his representation of the science this does not mean AGW is not happening. 

MOTR wrote on Mar 14^th, 2012 at 4:13am:


Great.
A beancounter, an ex politician and now a judge.
Everyone's an expert in 2012.

falah wrote on Mar 13^th, 2012 at 6:46pm:


Yes, As stated in that video someone posted, the earth's cycles been ice-age and warm periods are exagerated from the underlying cause of the warming for this very reason.

eg, an outside influence cause the earth to warm by 1 degree. This causes ice to melt and methane to be released, and the oceans ability to hold co2 decreased, causing an amplifing warming of 3 to 4 degrees.
Conversely a cooling influence of 1 degree causes more ice to form, reflecting more head, oceans absorb more co2, an we cool 3 or 4 degrees.

Enjoy Herr Docktor Jolly
‘
The fingerprint of anthropogenic greenhouse warming predicted by computer models is absent from real-world, observed trends in atmospheric temperature change
’


THE FACT of warming tells us nothing of the cause. Yet the scientific consensus is that, though the rapid climatic warming from 1906 to 1940 was a natural recovery from the historically low temperatures of the Little Ice Age, it is we who are chiefly to blame for the equally rapid warming from 1975 to the present. Since some climatologists challenge this consensus, can we settle the debate by predicting with models and then detecting by observation a characteristic “signature” in the climate data that allows us definitively to distinguish between anthropogenic and natural warming of the Earth’s atmosphere? This paper answers that key question.

To identify the distinctive signature of anthropogenic warming caused by greenhouse-gas emissions, we begin with a little elementary atmospheric physics.

The surface of the Earth does not cool primarily by thermal radiation. The main greenhouse gas, water vapor, generally maximizes at the surface in the tropics and sharply decreases with both altitude and latitude. There is so much greenhouse opacity immediately above the ground that the surface cannot effectively cool by the emission of thermal radiation.

Instead, heat is carried away from the surface by fluid motions ranging from the cumulonimbus towers of the tropics to the weather and planetary scale waves of the extratropics. These motions carry the heat upward and poleward to the “characteristic emission level” one optical depth into the atmosphere, known as τ=1. From here emitted thermal radiation can escape to space. Crudely speaking, the emitted thermal radiation is proportional to the fourth power of the temperature at the characteristic emission level.



How the greenhouse effect changes global temperature

τ is infrared absorption measured from the top of the atmosphere looking down. Diagram (a): When the earth is in radiative balance with space, net incoming solar radiation (NISR) is balanced by outgoing longwave radiation (OLR) from the characteristic emission level, τ=1. Diagram (b): When greenhouse gases are added to the atmosphere, the characteristic emission level is raised in altitude. Since atmospheric temperature decreases with altitude at about 10 ºC per mile, the new characteristic emission level is colder than the previous level. Therefore outgoing longwave radiation no longer balances net incoming solar radiation. The Earth is no longer in thermal balance with space. This imbalance is called “radiative forcing”. To re-establish balance, the temperature at the new τ=1 level must increase to about the temperature that had existed at the initial τ=1 level, which is typically 7-8 km in the tropics and lower elsewhere. The warming at τ=1 is the fundamental warming associated with the greenhouse effect. How warming at the characteristic emission level τ=1 relates to warming at the surface is not altogether clear, but computer models can be helpful here. Source: Lindzen (2007).



Computer models are able to assist us in distinguishing between the warming caused by adding greenhouse gases to the atmosphere and warming that is attributable to other causes.

The UN, in its 2007 climate assessment report, displays a series of plots of predicted rates of temperature change over the decades at altitudes from the Earth’s surface to 30 km, at latitudes from the South Pole via the Equator to the North Pole. Colors are used to illustrate the rates of change in temperature which the UN’s climate models predict, measured in degrees Celsius per decade. Each distinct cause of warming produces a visibly-distinct plot.

Six causes of atmospheric warming are considered. First, plots of natural warming caused by changes in total incoming solar radiation and changes in volcanic activity are shown, followed by plots of anthropogenic warming caused by emissions of greenhouse gases, changes in tropospheric and stratospheric ozone concentration, and the radiative forcing caused by sulphate aerosol particles (which actually cause cooling). Finally, the five plots of predicted warming are combined to create a single, sixth plot.

It is at once visible that the predicted warming caused by greenhouse-gas concentrations produces a pattern strongly distinct from other causes of warming. A “hot spot” appears between 8km and 12km of altitude in or near the tropics. At this computer-predicted “hot spot” high above the Earth, the UN’s models project that greenhouse warming will cause temperature to rise over the decades at a rate up to three times faster than at the surface.

Greenhouse warming is distinguishable from other forcings
hPa - Left hand side
km - Right hand side




Zonal mean simulated atmospheric temperature change (ºC per century, 1890-1999), from two natural causes, three anthropogenic causes and one combined cause, simulated by the UN’s PCM model. The “hot-spot” signature of greenhouse warming is visible in (c) and (f). (IPCC, 2007, p. 675, based on Santer et al, 2003. See also IPCC, 2007, Appendix 9C).


The UN’s diagram shows the pattern of zonal mean simulated atmospheric temperature change from 1890 to 1999, in °C per century from six causes –

‘
(a) natural radiative forcing from changes in solar activity;
(b) natural radiative forcing from changes in volcanic activity;
(c) anthropogenic radiative forcing from emissions of CO2 and other well-mixed greenhouse gases;
(d) anthropogenic radiative forcing from changes in tropospheric and stratospheric ozone;
(e) anthropogenic radiative forcing from pollutant sulphate aerosol particles emitted to the atmosphere; and
(f) all natural and anthropogenic forcings combined.
’

These six plots, from 1,000 hPa to 10 hPa barometric pressure (left scale), equivalent to 0-30 km (right scale), demonstrate that anthropogenic emission of well-mixed greenhouse gases, whether on its own (c) or combined with all other natural and anthropogenic forcings (f), is predicted to produce a signature distinct from that of other forcings alone. The reason why the combined-forcings plot (f) appears so similar to the greenhouse-gas forcing plot (c) is that the UN’s computer models predict that the impact of greenhouse-gas emissions on temperature is greater than that of all other forcings.

This instantly-recognizable “hot-spot” on the altitude-versus-latitude plot of predicted rates of temperature change is the unmistakable signature or characteristic fingerprint of greenhouse warming which we have been looking for. The warming which the computer models predict will arise from growing emissions of greenhouse gases is visibly distinct in its magnitude and in its altitudinal and latitudinal distribution from any other cause of natural or anthropogenic warming.

Following common meteorological practice, height is represented in these plots by atmospheric pressure level. Atmospheric pressure decreases approximately exponentially with height: 100 millibars corresponds roughly to 16 km; 200 mb to 12 km; 500 mb to 6 km; and 1000 mb to the surface. Predicted greenhouse-gas warming visibly peaks strongly in the tropical troposphere near the τ=1 characteristic emission level, which differs from one computer model another because the amount of water vapor differs among the models.

Within the tropical “hot-spot” at about 8 to 12 km altitude, the rate of increase in warming is more than twice and up to three times the rate of increase in warming at the Earth’s surface. This does not mean that absolute temperature in the mid-troposphere is greater than at the surface. Far from it: the temperature at altitude is very much colder than at the surface. But the rate at which temperature is predicted to increase in the “hot-spot” over the decades is two or three times the rate at which temperature is predicted to increase at the surface.

To put it another way, if we observe warming in the tropical upper troposphere, then the models predict that the contribution to warming at the surface that is caused by our greenhouse-gas emissions should be between less than half and one third of the warming seen in the upper troposphere. There is, of course, some greenhouse warming, indicated by the observed cooling of the stratosphere as less outgoing long-wave radiation reaches it. But the absence of the predicted “hot-spot” in the tropical mid-troposphere severely constrains the magnitude of the greenhouse warming.

It is worth noticing that if we considered only global temperatures, as many climatologists do, this signature of anthropogenic as distinct from natural warming would not become visible. Accordingly, the objections of Essex and McKitrick (2002) and Essex et al. (2007) to the use of globally averaged temperature are justifiable. Had we used globally averaged temperatures, it would have been almost impossible correctly to relate the underlying physics to the observations.

For you Herr Docktor Jolly


•      Labor's Political Ads Compromise CSIRO
19/10/11
At the Senate Economics Legislation Committee today the Deputy Chief Executive, CSIRO Operations, Mr Mike Whelan disclosed that the CSIRO was recruited by the Department of Climate Change and Energy Efficiency to help with the Government’s carbon tax advertising campaign. As a result Dr Alex Wonhas* appeared in these political ads.
The Public Research Agency Charter with the Commonwealth Scientific and Industrial Research Organisation states at point 6:
“….. They should not be asked by Government to defend or debate the merits of Government policy. As CSIRO employees, they should not advocate, defend or publicly debate the merits of government or opposition policies (including policies of previous Commonwealth governments, or state or local or foreign governments).”
Questions also need to asked of the Department of Climate Change and Energy Efficiency’s contribution to Labor’s carbon tax ads. The Australian Public Service Values and Code of Conduct in Practice states:
“Key Values: Relationships with Government and Parliament
• The APS is apolitical, performing its functions in an impartial and professional manner (s. 10(1)(a)).”
The Department of Climate Change and energy Efficiency’s role in spruiking the carbon tax ‘Party line’ has compromised the apolitical principles of the Public Service and brings into question the independence of Government bodies who engage in such behavior.
•      Dr Wonhas is the Director, Energy Transformed Flagship


•      
•      Chief Scientist Not Happy With Labor's International Science Cuts
19/10/11
Science Minister Kim Carr has suffered another humiliation this morning – with his own Chief Scientist indicating his displeasure with the Government’s abolition of Australia’s main international science program.
At a Senate Estimates hearing this morning, Chief Scientist Professor Ian Chubb said he was “building up to it” when asked if he intended to express his concern directly to Mr Carr about the axing of the International Science Linkages Program.
Extraordinarily, Mr Carr intervened in the questioning to protest that he had not terminated the nine-year-long, $94 million program – even though he decided to end the program’s funding in June this year. Under further questioning, Mr Carr was also forced to admit that no replacement program had been introduced.
The cessation of the program has already attracted criticism from across the Australian science community, including from the Australian Academy of Science (AAS).
AAS Secretary for Science Policy, Professor Bob Williamson, said in May this year that “the scientific links that we make with colleagues in other countries are the glue that maintains Australia's connections and prestige in the rest of the world … without a linkage program … our scientists will not be as respected, will not be able to collaborate and will not win a place at research forums internationally.''

Oh and yes...Herr Docktor...that was a very lame response to my last post. It is fact or it isn't...In the case of the information I posted, IT IS FACT!
    

For you Herr Docktor Jolly



But there isn't any conflict of interest, they protest, despite the fact that CSIRO provides a never-ending flow of alarmist predictions about climate change which will force Australia (and the world) to consider mitigation measures which might include, er, carbon sequestration:


THE head of the CSIRO is at the centre of conflict of interest claims over her role as a director of a Tasmanian company that purchases land for carbon sequestration.

It was revealed in Senate estimates today that the peak science body's chief executive Megan Clark is the director of Cradle Mountain Carbon Pty Ltd and is also on the board of Bank of America Merrill Lynch.

Cradle Mountain Carbon Pty Ltd is a private family company that sets aside land to store carbon as part of efforts to combat climate change.

Liberal senator David Bushby said at the very least the public perception of Dr Clark's additional appointments “should raise conflict of interest concerns”.

CSIRO's acting chief executive Mike Whelan said Dr Clark, who was absent from today's hearing, was an officer of the highest integrity and the organisation's board believed there was no conflict of interest issue.

“She is driven on the basis of values and integrity,” Mr Whelan said.

“I don't see, on the face of it, any issues there and I have no doubt the board has assured itself of the fact there is no conflict of interest.”

Well that's OK then. Silly of me to even think such a heresy! Move along, nothing to see here. Just like there's nothing to see at the IPCC, packed to the rafters with environmental activists… But we're really unbiased - honest! Just trust us! Nothing can go wrong!

And look at Whelan's immediate reaction - to defend Clark, and dismiss criticism with an arrogant wave of the hand. Instead, perhaps he should think, yes, it doesn't look good does it? Perhaps Clark should consider whether her directorship of this company really sends the right message, which may compromise the impartiality of the organisation, whether there is any real conflict of interest or not. Ha - fat chance of that.

Again, red baron refuses to post links.

What is he trying to hide I wonder.


For what its worth, a group of scientists like the CSIRO who distribute scientific findings will often sound similar to political movements which use scientific findings as a basis for decision making, and sound quite the opposite of political movements which wish to discredit all scientific studies because it could cost the money.

If the CSIRO was a lone voice you could argue local interference, but it is not. Its climate change  findings are all in-line with every other creditable scientific institution world wide.