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Andrew Glikson: The Lungs of the Earth

The Lungs of the Earth

by Andrew Glikson, November 1st, 2009

Figure 1. A plot of global mean temperature (increase above pre-industrial
time in degrees C) vs atmospheric greenhouse gas (GHG) concentration
(in CO2-eqivalent, a value which includes the effect of methane). The
assumed climate is 3+/-1.5 degrees C per doubling of CO2-e. The field I, II,
III, etc. correspond to the IPCC’s various emission scenarios. IPCC Climate
Change 2007: Synthesis Report, figure 5.1 ipcc.ch/graphics/syr/fig5-1.jpg

The recent warning by Professor Hans Joachim Schellnhuber, Director of the Potsdam Institute of Climate Impact: “We are simply talking about the very life support system of this planet” [1] is consistent with the lessons arising from the history of the Earth’s atmosphere/ocean system. A rise of CO2-e (CO2-equivalent, including the effect of methane) above 500 ppm and of mean global temperature toward and above 4 C, projected by the IPCC [2], Copenhagen [3] and Oxford [4] scientific reports, as well as reports by the world’s leading climate science bodies (NASA/GISS, Hadley-MET, Potsdam Climate Impact Institute, NSIDC, CSIRO, BOM), would transcend the conditions which allowed the development of agriculture in the early Neolithic, tracking toward climates which dominated the mid-Pliocene (3 Ma) (1 Ma = 1 million years) and further toward greenhouse Earth conditions analogous to those of the Cretaceous (145–65 Ma) and early Cenozoic (pre-34 Ma). Lost all too often in the climate debate is an appreciation of the delicate balance between the physical and chemical state of the atmosphere-ocean-land system and the evolving biosphere, which controls the emergence, survival and demise of species, including humans.

In contrast to Venus, with its thick blanket of CO2 and sulphur dioxide greenhouse atmosphere, exerting extreme pressure (90 bars) at the surface, or Mars with its thin (0.01 bar) CO2 atmosphere, the presence in the Earth’s atmosphere of trace concentrations of greenhouse gases (CO2, methane, nitric oxides, ozone) modulates surface temperatures in the range of -89 and +57.7 degrees Celsius, allowing the presence of liquid water and thereby of life.

Forming a thin breathable veneer only slightly more than one thousand the diameter of Earth, and evolving both gradually as well as through major perturbations with time, the Earth’s atmosphere acts as the lungs of the biosphere, allowing an exchange of carbon gases and oxygen with plants and animals, which in turn affect the atmosphere, for example through release of methane and photosynthetic oxygen.

An excess of carbon dioxide in the lungs triggers a need to breath. When the concentration of CO2 in the atmosphere rises above a critical threshold, the climate moves to a different state. Any significant increase in the level of carbon gases triggers powerful feedbacks. These include ice melt/warm water interaction, decline of ice reflection (albedo) effect and increase in infrared absorption by exposed water. Further release of CO2 from the oceans and from drying and burning vegetation shifts global climate zones toward the poles, warms the oceans and induces ocean acidification.

The essential physics of the infrared absorption/emission resonance of greenhouse molecules has long been established by observations in nature and laboratory studies, as portrayed in the relations between atmospheric CO2 and mean global temperature projections in Figure 1.

The living biosphere, allowing survival of large mammals and of humans on the continents, has developed when CO2 levels fell below about 500 ppm some 34 million years ago (late Eocene). At that stage, and again about 15 million years ago (mid-Miocene), development of the Antarctic ice sheet led to a fundamental change in the global climate regime.

About 2.8 million years ago (mid-Pliocene) the Greenland ice sheet and the Arctic Sea ice began to form, with further decline in global temperatures expressed through glacial-interglacial cycles regulated by orbital forcing (Milankovic cycles), with atmospheric CO2 levels oscillating between 180 and 280 ppm CO2 [5]. These conditions allowed the emergence of humans in Africa and later all over the world [6].

Humans already existed 3 million years-ago, however these were small clans which, in response to changing climates migrated to more hospitable parts of Africa and subsequently Asia [6]. About 124 thousand years ago, during the Emian interglacial, temperatures rose by about 1 degree C and sea levels by 6-8 meters.
The development of agriculture and thereby human civilization had to wait until climate stabilized about 8000 years ago, when large scale irrigation along the great river valleys (the Nile, Euphrates, Hindus and Yellow River) became possible.

Since the industrial revolution humans dug, pumped and burnt more than 320 billion tons of carbon which accumulated as the result of biological activity during 400 million years. 320 billion tons of carbon is more than 50% the carbon concentration of the original atmosphere (540 billion tons). As a consequence the level of CO2 in the atmosphere has risen by about 40%, from 280 to 388 ppm.

The world is now witnessing a dangerous shift in the state of the atmosphere-ocean system, an extremely rapid change from the interglacial condition of the Holocene, which began about 11,700 years-ago, to conditions analogous to those of the mid-Pliocene when mean global temperatures were 2-3 degrees C higher, and sea levels about 25 +/- 12 meters higher, than the early 20th century.

In terms of the combined effects of CO2, methane and nitric oxide, the rise of greenhouse gases has reached about 460 ppm CO2-equivalent (CO2-e) (Figure 1), only slightly below the 500 ppm level which correlates with the maximum stability of the Antarctic ice sheet.

The current rate at which CO2 is rising, 2 ppm per year, is unprecedented in the recent history of the Earth, with the exception of the onset of greenhouse atmospheric conditions following major volcanic episodes and asteroid and comet impacts, which led to the large mass extinctions in the history of the Earth (end-Ordovician, end-Devonian, end-Permian and Permian-Triassic boundary, end-Triassic, end-Jurassic, end-Cretaceous) (Figure 2).

Further rise of CO2-e above 500 ppm and mean global temperatures above 4 degrees C can only lead toward greenhouse Earth conditions such as existed during the Cretaceous and early Cenozoic (Figure 2).
At 4 degrees C advanced to total melting of the Greenland and Antarctic ice sheets leads to sea levels tens of meters higher than at present.

Since the 18th century mean global temperature has risen by about 0.8 degrees C. Another 0.5 degrees C is masked by industrial-emitted aerosols (SO2), and further rise ensues from current melting of the ice sheets and sea ice, with loss of reflection (albedo) of ice and gain in infrared absorption by open water, leading to feedback effects.

The polar regions, actinv as the “thermostats” of the Earth, are the source of the cold air current vortices and the cold ocean currents, such as the Humboldt and California current, which keep the Earth’s overall temperature balance, much as the blood stream regulates the body’s temperature and the supply of oxygen.

Unfortunately climate change is not an abstract notion, with consequences manifest around the globe in terms of (1) Polar ice melt; (2) Sea level rise; (3) Migration of climate zones toward the poles; (4) Desertification of temperate climate zones; (5) Intensification of hurricanes and floods, related to increase in the level of atmospheric energy; (6) acidification of the oceans; (7) Destruction of coral reefs [2-4].

Which is why the European Union and in recent international conferences defined a rise by 2.0 degrees C as the maximum permissible level. A dominant scientific view has emerged that atmospheric CO2 levels, currently at 388 ppm, need to be urgently reduced to below 350 ppm [5]. This is because, a rise of CO2 concentration above 350 ppm triggers feedback effects, which include:
    1. Carbon cycle feedback due to warming, which dries and burns vegetation, with loss of CO2. With further warming, the onset of methane release from polar bogs and sediments is of major concern.2. Ice/melt water interaction feedbacks: melt water melts more ice, ice loss results in albedo loss, exposed water absorb infrared heat. Because CO2 is cumulative, with atmospheric residence time on the scale of centuries to millennia, it may not be possible to stabilize or control the climate through small incremental reduction in emission and avoid irreversible tipping points [7]. Humans can not argue with the physics and chemistry of the atmosphere. Time is running out. What is needed are global emergency measures, including:1. Urgent deep cuts in carbon emissions by as much as 80%.2. Parallel Fast track transformation to non-polluting energy utilities – solar, solar-thermal, wind, tide, geothermal, hot rocks.3. Global reforestation and re-vegetation campaigns, including application of biochar.
Business as usual, with its focus on the annual balance sheet, can hardly continue under conditions of environmental collapse. Governments, focused on the next elections, need to focus on the survival of the next generation.

Good planets are hard to come by.
http://ecoworldly.com/2009/10/02/is-the-us-climate-illiterate/ ; http://www.nature.com:80/climate/2009/0911/full/climate.2009.106.html ;

IPCC 2007 AR4 - http://www.ipcc.ch/publications_and_data/publications_and_data_reports.htm
Copenhagen Synthesis Report http://www.anu.edu.au/climatechange/content/news/copenhagen-synthesis-report-released-today/
Oxford 28-30 October, 2009 meeting http://www.eci.ox.ac.uk/4degrees/programme.php
Hansen et al. 2008. Target CO2: Where Should humanity aim? http://www.columbia.edu/~jeh1/2008/TargetCO2_20080407.pdf ; Glikson, A.Y., 2008. Milestones in the evolution of the atmosphere with reference to climate change. Aust. J. Earth Sci. 55 no. 2. http://www.zeroemissionnetwork.org/files/MILESTONES_19-6-07.pdf
deMenocal, P.B. African climate change and faunal evolution during the Pliocene-Pleistocene. Earth and Plant. Sci. Lett, Frontiers, 6976, 1-22, 2004 http://www.ldeo.columbia.edu/~peter/Resources/Publications/deMenocal.2004.pdf
Lenton et al., 2008. Tipping points in the Earth climate system. http://www.sciencedaily.com/releases/2008/02/080204172224.htm
Royer et al., 2004. CO2 as a primary driver of Phanerozoic climate. GSA Today; v. 14; no. 3, doi: 10.1130/1052-5173
Berner et al., 2007. Oxygen and evolution. Science 316, 557 – 558. http://www.vancouver.wsu.edu/fac/bishop/Teaching/A%20Biol403-2008/Readings/Oxygen%20Berner%20Ward%202007.pdf


Figure 2. Variations in atmospheric CO2 concentrations and oxygen concentrations correlated with ice ages (blue histograms, extending according to geographic latitude). Note the sharp decline in atmospheric CO2 during ice ages. After Royer et al. 2004 [8] and Berner et al. 2007 [9].

-###-
by Andrew Glikson
Earth and paleoclimate scientist
Institute of Climate Change
Australian National University
Canberra, A.C.T. 0200

Link:  http://www.thepeoplesvoice.org/TPV3/Voices.php/2009/11/01/the-lungs-of-the-earth

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Andrew Glikson: Planetary Boundaries (CO2 equivalent of 460 ppm has been surpassed

Planetary Boundaries

by Andrew Glikson, Novakeo.com, October 18, 2009

The CO2 & 350 ppm Upper Limit of Human Habitats…

THE RISE OF ATMOSPHERIC CO2 ABOVE 350 ppm AT THE CURRENT RATE OF 2 ppm/yr IS TRANSCENDING ENVIRONMENTAL CONDITIONS WHICH ALLOWED THE DEVELOPMENT OF HUMAN CIVILIZATION AND, WITH LAG EFFECTS, IS LEADING TOWARD AN ICE-FREE EARTH AND A MASS EXTINCTION OF SPECIES
earthClimate change is tracking toward levels which transcend the planetary boundaries which allowed the development of humans over the last 3 million years [1]. These limits have already been crossed in terms of the rise in greenhouse gases (CO2, methane, nitric oxide) and extensive loss of species [1]. Given lag effects, looming threats include (A) ocean acidification and phosphorous flux, collapse of coral reefs and the marine food chain; (B) availability of freshwater; (C) conversion of natural forests to cropland, i.e. the Amazon; (D) ozone depletion; (E) atmospheric aerosol loading and (F) chemical pollution by metals, plastics, radioactive nuclei, etc.

The rate of climate change since the mid-1970s, at up to ~2 ppm CO2 per-year, reaching 388 ppm CO2 and ~460 ppm CO2-equivalent (including methane), is leading toward ~1.5 °C mean global temperature rise relative to pre-industrial time. This results in carbon cycle and ice/water feedback processes, with consequent (A) extreme rates of polar ice melting, including the Arctic Sea, Greenland, West and East Antarctica [2], which threatens accelerated sea level rise; (B) a progressive shift of climate zones toward the poles, extending the tropics as indicated by intensified cyclones and floods, and enlarging desert regions as manifested by extreme droughts and fires, including in Australia.

The consequences for human habitats include loss of arable land, fresh water supplies and extreme weather events. The loss of Himalayan snow and thereby decreased river flow, coupled with a failure of the monsoon and sea level rise, threatens more than one billion people in south and southeast Asia. As the polar regions warm [3], the release of methane from the many hundreds of billions of tons of carbon stored in permafrost and shallow lakes and seas, is underway.

Reports by the world’s leading climate research organizations (Hadley-Met, Tyndall, NASA/GISS, Potsdam, NSIDC, CSIRO, BOM) and in thousands of papers in the peer-reviewed scientific literature demonstrate the anthropogenic origin of climate change since the industrial revolution, accelerating since the mid-1970s, beyond reasonable doubt [4]. The Australian continent, dominated by subtropical arid zones, is in particular danger from extending tropical floods in the north and progressive desertification and fires in the south.

Humans and species can adapt to gradual changes in the environment, and our prehistoric ancestors were able to migrate over much of the world through extreme glacial-interglacial changes. This is not the case with the 6 billion members of present-day civilization, anchored as they are to coastal and valley agricultural lands. The consequences of the extreme rise rate of CO2 at 2 ppm/year will greatly complicate adaptation.

In my view an upper limit of 450 ppm CO2, proposed by a range of reports by government organizations, including the Garnaut Review [5] and the Australian Government White Paper [6], can not be sustained, for the following reasons:

A. The atmosphere has already transcended the CO2-equivalent (including the forcing of methane) level of 460 ppm.

B. A level of 450 ppm CO2 is a mere ~40 ppm below the upper boundary of ~500 ppm, which is the upper limit of stability of the Antarctic ice sheet, formed about 34 million years ago. In the Pliocene, 3 million years ago, a CO2 level of 400 ppm led to temperature rise of about 2–3 °C and sea level rise of 25+/-12 meters.

C. There is no evidence that the climate can be “stabilized” at such high level of greenhouse-induced forcing. Due to carbon cycle feedback loops and feedbacks related to ice melt/water interaction, CO2 level of 450 ppm may lead to yet higher greenhouse levels, high temperature levels and possible tipping points.

D. Not taken into account in many projections are looming emissions of methane, which are already taking place under atmospheric CO2 levels of 388 ppm, or CO2-e levels of 460 ppm.

In the view of leading US climate scientists there is no alternative to attempts at reducing atmospheric CO2 levels to below 350 ppm as soon as possible [8]. In my view, only a combination of (A) deep urgent cuts in carbon emissions; (B) fast-track development of clean renewable energy systems; (C) an intensive reforestation campaign; (D) application of a range of biosequestration measures, including chemical sequestration and carbon draw-down methods, may be able to prevent further carbon cycle and ice melt feedback effects from triggering dangerous tipping points [9] with tragic consequences.

1.      Schellnhuber, Oxford meeting, 28-30.10.09 http://www.eci.ox.ac.uk/4degrees/programme.php
2.       British Antarctic Survey, 23.9.09
http://www.antarctica.ac.uk/press/press_releases/press_release.php?id=989
3.       Polar regions have warmed by a mean of up to 4 degrees Celsius since the mid-20th century (NASA/GISS). http://data.giss.nasa.gov/gistemp/
4.       Contrary arguments, by a handful of climate change denialists, are unreferenced or derived by deceptive alteration of scientific data.
5.       Garnaut Review. http://www.garnautreview.org.au/domino/Web_Notes/Garnaut/garnautweb.nsf
6.       White Paper/CPRS http://www.climatechange.gov.au/whitepaper/index.html
7.       Copenhagen Synthesis Report http://www.anu.edu.au/climatechange/content/news/copenhagen-synthesis-report-released-today/
8.       Hansen et al. 2008. Target CO2: Where Should humanity aim? http://www.columbia.edu/~jeh1/2008/TargetCO2_20080407.pdf
9.       Lenton et al., 2008. Tipping points in the Earth climate system. http://www.sciencedaily.com/releases/2008/02/080204172224.htm

Dr. Andrew Glikson is a Earth and paleo-climate research scientist at Australian National University. He spends much of his free time invested in efforts to address climate change issues in a timely fashion and can be contacted at: geospec@iinet.net.au.

Dr. Andrew Glikson is a regular columnist for Novakeo.com

Link:  http://novakeo.com/?p=5086

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Andrew Glikson: Global warming toward 2 degrees centigrade

According to the IPCC AR4-2007 report [1], a total anthropogenic greenhouse factor of 3.06 Watt/m², equivalent to about +2.3 °C, is masked by a compensating aerosol albedo effect of -1.25 Watt/m² (mainly sulphur from industrial emissions), equivalent to about -0.9 °C (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 °C occurs), mean global temperatures track toward +2 °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 °C, an order of magnitude less than greenhouse forcing. Sharp peaks include the 1998 El-Nino peak (near +0.55 °C) and the 2007 La Nina trough (near -0.7 °C) [2]. Mean global temperature continued to rise during 1999-2005 by about 0.2 °C. 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 km² during 2000-2009 [3].

(B) Increase in Greenland September ice melt area from 350,000 to 550,000 km² during 1997-2007 [4].

(C) Warming of the entire Antarctic continent by 0.6 °C and of west Antarctic by 0.85 °C during 1957-2006 [5], reflected by collapse of west Antarctic ice shelves [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 (http://earthobservatory.nasa.gov/Features/WorldOfChange/sea_ice_south.php?src=eoa-ann).

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, 19].

PeriodCO2 ppm
Forcings (Watt/m²)		Temperature oC (1 oC ~ ¾ W/m2)Sea level
(m)
1750-2005260-387Greenhouse: +3.06
Albedo: -1.25*
Current balance: +1.81
Ice albedo loss (? W/m2)		~ +2.3 ~-0.9?T oCTracking toward Pliocene levels
Last glacial termination (20-11.7 kyr)180-280Greenhouse 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 implication s 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 "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 authorities are 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 current targets to 'Russian roulette with the climate system with most of the chambers loaded'.

[1] http://www.ipcc.ch/ ; SPM.2.

[2] http://data.giss.nasa.gov/gistemp/graphs/Fig.C.lrg.gif

[3] http://www.nasa.gov/topics/earth/features/arctic_thinice.html

[4] http://nsidc.org/data/virtual_globes/

[5] http://www.giss.nasa.gov/research/news/20090121/

[6] http://nsidc.org/news/press/20080325_Wilkins.html

[7] http://climatechangepsychology.blogspot.com/2009/02/timothy-m-lenton-et-al-pnas-105-6.html ; http://researchpages.net/ESMG/people/tim-lenton/tipping-points/.

[8] http://www.indiana.edu/~halllab/L577/Topic3/Dakosetal_2008_PNAS.pdf

[9] http://www.worldclimatereport.com/index.php/2009/01/23/glacier-slowdown-in-greenland-how-inconvenient/

[10] http://www.connorcourt.com/catalog1/index.php?main_page=product_info&cPath=7&products_id=103 ; http://scienceblogs.com/deltoid/2009/05/ian_enting_is_checking_plimers.php http://bravenewclimate.com/2009/04/23/ian-plimer-heaven-and-earth/ ; http://www.theaustralian.news.com.au/story/0,,25433059-5003900,00.htmlhttp://www.crikey.com.au/2009/05/05/plimer-wants-to-talk-science-ok-here-goes/

[11] http://australianconservative.com/main-site/category/policy/environment/page/2/

[12] http://www.e360.yale.edu/content/feature.msp?id=2154

[13] http://climatecongress.ku.dk/newsroom/congress_key_messages/

[14] http://www.theaustralian.news.com.au/story/0,,25037352-7583,00.html?from=public_rss

[15] http://johnquiggin.com/index.php/archives/2009/04/24/doolittle-and-delay/

[16] http://www.thewest.com.au/default.aspx?MenuID=28&ContentID=139318 http://wotnews.com.au/like/7_australian_climate_scientists_forecast_an_end_to_coal/3359286/.

[17] http://www.abc.net.au/worldtoday/content/2008/s2543405.htm

[18] http://www.safecom.org.au/csiro-silence.htm

[19] http://pubs.giss.nasa.gov/abstracts/2008/Hansen_etal.html

Link to article: http://www.opednews.com/articles/GLOBE-WARMING-TOWARD-TWO-D-by-Andrew-Glikson-090531-738.html

Written by fatih al-farahat in , ,


Andrew Glikson's blog on climate change science and issues

Andrew Glikson's blog

Can Obama’s carbon caps bridge Antarctic’s ice shelf gaps? April 8, 2009
Obama, the EU (and Rudd?) face two issues: first the plethora of extreme weather events around the world, including fatal fires and floods, inherent in accelerating climate change, and second, a massive well-funded disinformation campaign, which has provided governments an excuse to undertake no mitigation measures or over more than 20 years.



While Rome burns, March 25, 2009
There is little evidence the “climate change skeptics” worry too much their misunderstanding of climate science may lead to the death of billions and the likely demise of civilization . The legal status of disinformation campaigns aimed at the promotion of substances of proven fatal global consequences, such as ozone-destroying CFCs, or greenhouse gas levels pushed up to near-40% above their natural level, is unclear. The lack of suitable laws to prevent ecocide may yet prove to be the Achilles heel of global civilization.




References (Antarctic Blues and the Australian Drought), February 16, 2009
Antarctic blues and the Australian drought, February 16, 2009
Until recently, whenever climate research organizations reported increases in Arctic Sea ice melt rates , advocates of global “cooling” have been making references to the Antarctic continent as supposed counter argument. Referring to small stable or slightly cooling parts of east Anarctica, a plethora of bogus climate websites claim Antarctic warming is not a part of global warming. Presumably regarding Antarctica as part of another planet?



Planet eaters: Chain reactions, black holes and climate change, January 21, 2009
Planetcide challenges every faith, ideal and social system humans ever held. Individuals are crushed, as in H. G. Wells’ War of the Worlds, when cells rebelling against the insanity of a murderous global Martian society are destroyed by the parent organism.



The Faustian Bargain, January 12, 2009
The sensitivity of the Earth’s atmosphere to anthropogenic carbon gases has been underestimated. As the orgy of burning carbon products of 400 million of biological evolution continues unabated, pushed by business, advertisers and consumption-promoting governments, global warming proceeds at a pace faster than projected by the IPCC, tracking toward likely climate tipping points.



Link to blog: http://webdiary.com.au/cms/?q=blog/1737

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Andrew Glikson: Antarctic blues and the Australian drought

Antarctic blues and the Australian drought

Antarctic blues and the Australian drought
Andrew Glikson
Earth and paleo-climate scientist
Australian National University

The Antarctic ice sheet has not always been there.

The ice began to form about 34 million years ago, by the late Eocene, when the Antarctic continent (Fig. 1) became isolated through the opening of the Drake Passage between the Antarctic peninsula and southern tip of South America, restricting access of warm currents, and when global carbon dioxide levels decreased to below 450 parts per million CO2, decreasing the mean temperature of Earth by near -6 °C [1].

Fig. 1. The Antarctic continent from space

The current global rise in atmospheric CO2 levels to 387 ppm (over 400 ppm-e radiative equivalent of CO2 + CH4 + N2O) ensues in warming of the Antarctic ice, in particular of western Antarctica, and of the Antarctic peninsula (Fig. 2). It further reduces concentration of circum-Antarctic sea ice (Fig. 3). Another expression of warming is the accelerating movement of glaciers, where the mass of the ice sheet decreased significantly at a rate of 152 ± 80 cubic kilometers of ice per year [2].

Based on a combination of ground stations and satellite observations, NASA/GISS reports a mean temperature increase of +0.12 °C per decade for the entire continent of Antarctica, and +0.17 °C per decade for western Antarctica, during 1957-2006 (NASA, 21.1.2009) (Fig. 2). Manifestations of warming include reduced concentration of sea ice around parts of Antarctica (Fig. 3) and the disintegration of ice shelves (Fig. 4) due to the effect of warming seas. In particular, the part of western Antarctica which overlies sub-sea level basement is vulnerable to sea water-induced melting. While most of the peripheral near-coastal zones of west and east Antarctica display various degrees of warming and glacier melt, a small area in east Antarctica have been cooling, a likely result of ozone depletion above Antarctica, ozone being a greenhouse gas, as well as acceleration and wind-chill effect of the Antarctic wind vortex (Fig. 5).

Fig. 2. NASA Goddard Institute of Space Science, 21.1.2009. Satellite and ground station data confirm 50 years of west Antarctica warming. Values in °C over 50 years

Fig. 3. Sea ice per cent concentration trends in the Arctic Sea and around Antarctica for October 2008 relative to 1979-2000 October monthly average. National Snow and Ice Data Center.

Regional changes in atmospheric circulation and associated changes in sea surface temperature and sea ice are required to explain the enhanced warming in Western Antarctica [3]. Breakup of ice shelves is exemplified by the Wilkins ice shelf (Fig. 4), which for the first time continued to breakdown during winter (June-July) 2008 [4].

Fig. 4. Satellite images shows the Wilkins Ice Shelf as it began to break up. The large image is from March 6; the images at right, from top to bottom, are from February 28, February 29, and March 8. NSIDC processed these images from the NASA Moderate Resolution Imaging Spectroradiometer (MODIS) sensor, which flies on NASA’s Earth Observing System Aqua and Terra satellites.

The southward migration of climate zones by nearly 400 km and the retreat of the Antarctic wind vortex (Fig. 5) have combined to increase drought conditions in southern Australia. In the last thirty years, a 20% loss of the average rainfall along Australia's southern fringe occurred, marked by sudden drops in rainfall in southwestern Australia in the 1970s, and in Victoria in the 1990s, affecting agriculture and reservoir supplies for more than six million people [5]. The consequences in terms of maximum temperature rise (Fig. 6A), rainfall variations (Fig. 6B), and extreme heat wave conditions (Fig. 6C) are evident.

Figure 5. The Antarctic wind vortex viewed from the Galileo spacecraft. As climate zones migrate toward the poles, the southward contraction of the swirling cold moist fronts results in reduced rainfall over southern Australia.

Loss of Antarctic ice shelves and ice sheets, indicated by time variable gravity show mass loss [2] threatens to raise sea levels on the scale of many metres, leading to inundation of coastal regions, deltas, and low river valleys around the world (Fig. 7). Melting of western Antarctic ice would raise sea levels by nearly 7 metres, whereas melting of the entire Antarctic ice sheet would raise sea levels by some 70 metres, returning the Earth to pre-late Eocene conditions (Fig. 6).

Figure 6A. Australia maximum temperature variations in °C per 10 years, 1970-2008 (Australian Bureau of Meteorology).

Figure 6B. Australia annual total rainfall variations in mm per 10 years, 1970-2008 (Australian Bureau of Meteorology).

Figure 6C. Maximum temperatures for Australia, 7 February 2009. Australian Bureau of Meteorology.

Fig. 7. Projected sea level rise (Hansen, 2007). The color bars represent topographic elevations in metres. Sea level rise by up to 25 metres (Greenland and western Antarctic ice melt) is represented in blues, and up to 75 metres (total Antarctic melt) in yellow.

Until recently, whenever climate research organizations reported increases in Arctic Sea ice melt rates [6], advocates of global “cooling” have been making references to the Antarctic continent as a supposed counter argument [7]. Referring to small, stable or slightly cooling parts of east Anarctica (Fig 2), a plethora of bogus climate websites claims Antarctic warming is not a part of global warming [8].

Presumably regarding Antarctica as part of another planet?

Nor do “climate skeptics” shed too many tears about Emperor penguins, the magnificent birds which have to migrate from their inland colonies across ice shelves and sea ice (Fig. 8), where the females lay just one egg that is tended by the male. The ice plays a major role in their overall breeding success. Further, the extent of sea ice cover influences the abundance of krill and the fish species that eat them – both food sources for the penguins.

Misreadings of climate science by “climate skeptics” have delayed efforts at climate mitigation by at least 20 years. In the words of Clive Hamilton [9]: “If scientific advances cause scientists to reject the conclusions of past IPCC reports … not much harm will be done. … but if … fellow skeptics were successful in stopping policies to cut emissions and the IPCC projections turn out to be correct, then environmental catastrophe will follow and millions of people will die. Do they lose sleep over this? Do they worry about how their grandchildren will see them? Or are they so consumed by the crusade that they know they will never be proven wrong?”

Fig. 8. Melting Antarctic iceberg.

References

Link to this article: http://webdiary.com.au/cms/?q=node/2725

Written by fatih al-farahat in ,


Andrew Glikson: Dangerous climate change

[BLOGGER'S NOTE: This post is excerpted from a much larger article -- please see the link below for more information.]

Climate change post-1750 is driven by total radiative forcing tracking toward ca. 3 Watt/m2, near-half the forcing of 6.5±1.5 Watt/m2 associated with the last glacial termination (ca. 14.7–11.7 kyr ago). Given the onset of the Antarctic ice sheet at or below 450 ppm CO2 ca. 34 million years ago (Ma) (late Eocene), and of Arctic Sea ice below 400 ppm ca. 2.8 Ma (mid-Pliocene), the projected consequences of CO2 trajectories toward 550 or 650 ppm through the 21st century, now considered inevitable by governments, likely involve a return to Pliocene conditions (+ 2–3 oC; + 25±12 m sea level rise; permanent El Nino) through likely climate tipping points. Depending on the degree of methane (CH4) release from sediments, permafrost and tropical bogs, developments analogous to the PETM (Paleocene-Eocene Thermal Maximum, 56 Ma; + 6 oC) and attendant mass extinctions may ensue. The Intergovernmental Panel for Climate Change (IPCC) 2007 projections underestimate ice melt and sea level rise parameters. The Garnaut-2008 Report takes limited account of the effects of methane release from permafrost and shallow polar ocean sediments and the synergy of carbon cycle feedbacks and ice melt/water feedbacks, as indicated by the recent climate history of Earth. Assumption of CO2 and climate 'stabilization' and possible reversal on decadal time scale are difficult to reconcile with the sharp transitions between climate states observed in the recent history of the atmosphere. The opening of an ice-free Arctic ocean and slow-down or aborting of the North Atlantic thermohaline circulation lead to a new climate regime in the Northern Hemisphere, possibly similar to events ca. 8.2 kyr ago when ice-melt currents resulted in several degrees cooling and freezing of Europe. According to Anderson and Bows (2008), it may be too late to arrest climate change by reduced carbon emission alone. Humanity needs to fast-track development of techniques for atmospheric CO2 down-draw to levels ca. 350 ppm and below (Hansen et al., 2008).

Link to the rest of this article:
http://www.opednews.com/articles/Dangerous-Climate-Change--by-Andrew-Glikson-081206-176.html