Archive for September 2009

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The Greenland ice sheet is shrinking

The Greenland ice sheet is shrinking



Satellite readings show Greenland is losing large quantities of ice. The enormous ice cap constituting the inland ice is melting at an ever-increasing rate, and there is every indication that the inland ice is contributing to the rise in sea level of the oceans.

An enormous net loss

Scientists are monitoring developments using satellites, light aircraft and observations on the ice, and most agree that global warming is the cause of this melting.

At the heart of the problem is the fact that ice formation occurring on the inland ice as a result of winter snowfalls cannot compensate for the melting. In other words, there is a net loss of ice. Calculations by a Dano–US team of scientists show an annual volume loss of about 257 km³.

The average net loss of ice in 2080 will have reached 465 km³ – a loss of ice 80% greater than today, research scientists of the International Arctic Research Center, Fairbanks, Alaska, state to Ritzau.

The melting is accelerating

A specific example of the situation is that twice as much ice melted in 2007 as was the case just three years earlier. In general, the region where there is increased melting has grown considerably in recent years. The melting has mainly occurred in the southern part of the inland ice and at the edges of the ice up to 3 km in height.

Glaciers are calving sooner

Readings show that the periphery of the inland ice is accelerating outwards. Therefore, the glaciers are calving sooner and more violently than before, and enormous icebergs are forming.

At the same time, the fronts of the largest glaciers are receding. This is due to a rise in summer temperatures. Only very little additional heat would be required for the snow covering large areas to disappear. A temperature increase of 1 °C distributed evenly across the large ice cap is enough to melt a vertical metre of ice each year. In other words, this would require one additional metre of ice to form from winter snowfalls in order to prevent the glacier from receding.

Measuring the ice

In the past, it was incredibly expensive and difficult to collect accurate information on the melting of the inland ice. In recent years, however, advanced satellites have made it possible to gather very accurate data, and a GPS network, GNET, positioned along the edge of the inland ice will provide data for use in calculations. GNET, which will be completed in 2010, is being established as a collaborative venture involving research scientists from the US, Luxembourg and Denmark.

GEUS is leading an ongoing monitoring programme (Programme for Monitoring of the Greenland Ice Sheet (PROMICE)that combines readings from GPS stations with data from aircraft and satellites to equip scientists to calculate the combined mass loss of the inland ice on an annual basis.

Meltwater in the sea

The inland ice is releasing increasing amounts of fresh water into the North Atlantic, which has a major impact on global ocean currents. This could have inherent consequences for the global climate, but no one knows exactly how or to what extent.

Professor Dorte Dahl-Jensen of the Niels Bohr Institute at the University of Copenhagen believes sea levels may rise by almost 1 m by the year 2100. The IPCC, the UN Intergovernmental Panel on Climate Change, is of the opinion that the maximum rise in sea level this century will probably be around 59 cm.

In Dorte Dahl-Jensen's opinion, the Panel on Climate Change has underestimated the melting of the inland ice. The Panel has first and foremost calculated the effect of melted sea ice. She expects 30 cm to come from the melting of the ice on Greenland and 30 cm from melting in Antarctica. The rest will come from small glaciers, and as a consequence of the water in the sea expanding as it warms.

Link to article:  http://climategreenland.com/klimaforandringer/indlandsisen_skrumper/&new_language=1

Written by fatih al-farahat in


UNEP: Impacts of climate change coming faster and sooner: New science report underlines urgency for governments to seal the deal in Copenhagen

Impacts of climate change coming faster and sooner: New science report underlines urgency for governments to seal the deal in Copenhagen

Washington/Nairobi, 24 September 2009 -The pace and scale of climate change may now be outstripping even the most sobering predictions of the last report of the Intergovernmental Panel of Climate Change (IPCC).


An analysis of the very latest, peer-reviewed science indicates that many predictions at the upper end of the IPCC's forecasts are becoming ever more likely.


Meanwhile, the newly emerging science points to some events thought likely to occur in longer-term time horizons, as already happening or set to happen far sooner than had previously been thought.


Researchers have become increasingly concerned about ocean acidification linked with the absorption of carbon dioxide in seawater and the impact on shellfish and coral reefs.


Water that can corrode a shell-making substance called aragonite is already welling up along the California coast decades earlier than existing models predict.


Losses from glaciers, ice-sheets and the Polar Regions appear to be happening faster than anticipated, with the Greenland ice sheet, for example, recently seeing melting some 60% higher than the previous record of 1998.


Some scientists are now warning that sea levels could rise by up to two metres by 2100 and five to ten times that over following centuries.


There is also growing concern among some scientists that thresholds or tipping points may now be reached in a matter of years or a few decades including dramatic changes to the Indian sub-continent's monsoon, the Sahara and West Africa monsoons, and climate systems affecting a critical ecosystem like the Amazon rainforest.


The report also underlines concern by scientists that the planet is now committed to some damaging and irreversible impacts as a result of the greenhouse gases already in the atmosphere.


Losses of tropical and temperate mountain glaciers affecting perhaps 20-25% of the human population in terms of drinking water, irrigation and hydro-power.


Shifts in the hydrological cycle resulting in the disappearance of regional climates with related losses of ecosystems, species and the spread of drylands northwards and southwards away from the equator.


Recent science suggests that it may still be possible to avoid the most catastrophic impacts of climate change. However, this will only happen if there is immediate, cohesive and decisive action to both cut emissions and assist vulnerable countries adapt.


These are among the findings of a report released today by the United Nations Environment Programme (UNEP) entitled Climate Change Science Compendium 2009.


The report, compiled in association with scientists around the world, comes with less than 80 days to go to the crucial UN climate convention meeting in Copenhagen, Denmark.


In a foreword to the document, the United Nations Secretary-General, Ban Ki-moon, who this week hosted heads of state in New York, writes, "This Climate Change Science Compendium is a wake-up call. The time for hesitation is over."
 

"We need the world to realize, once and for all, that the time to act is now and we must work together to address this monumental challenge. This is the moral challenge of our generation."


The Compendium reviews some 400 major scientific contributions to our understanding of Earth Systems and climate change that have been released through peer-reviewed literature, or from research institutions, over the last three years.


Achim Steiner, UN Under-Secretary General and UNEP Executive Director, said, "The Compendium can never replace the painstaking rigour of an IPCC process -- a shining example of how the United Nations can provide a path to consensus among the sometimes differing views of more than 190 nations."


"However, scientific knowledge on climate change and forecasting of the likely impacts has been advancing rapidly since the landmark 2007 IPCC report," he added.


"Many governments have asked to be kept abreast of the latest findings. I am sure that this report fulfils that request and will inform ministers' decisions when they meet in the Danish capital in only a few weeks time," said Mr. Steiner.


The research findings and observations in the Compendium are divided into five categories: Earth Systems, Ice, Oceans, Ecosystems and Management. Key developments documented since the IPCC Fourth Assessment Report include:


Earth Systems


A new climate modeling system, forecasting average temperatures over a decade by combining natural variation with the impacts of human-induced climate change, projects that at least half of the 10 years following 2009 will exceed the warmest year currently on record. This is despite the fact that natural variation will partially offset the warming "signal" from greenhouse gas emissions.


The growth in carbon dioxide emissions from energy and industry has exceeded even the most fossil-fuel intensive scenario developed by the IPCC at the end of the 1990s. Global emissions were growing by 1.1% each year from 1990-1999 and this accelerated to 3.5% per year from 2000-2007.


The developing and least-developed economies, 80% of the world's population, accounted for 73%of the global growth of emissions in 2004. However, they contributed only 41% of total emissions, and just 23% of cumulative emissions since 1750.


Growth of the global economy in the early 2000s and an increase in its carbon intensity (emissions per unit of growth), combined with a decrease in the capacity of ecosystems on land and the oceans to act as carbon "sinks," have led to a rapid increase in the concentrations of carbon dioxide in the atmosphere. This has contributed to sooner-than-expected impacts including faster sea-level rise, ocean acidification, melting Arctic sea ice, warming of polar land masses, freshening of ocean currents and shifts in the circulation patterns of the oceans and atmosphere.


The observed increase in greenhouse gas concentrations are raising concern among some scientists that warming of between 1.4 and 4.3 °C above pre-industrial surface temperatures could occur. This exceeds the range of between 1 and 3 degrees perceived as the threshold for many "tipping points," including the end of summer Arctic sea ice, and the eventual melting of Himalayan glaciers and the Greenland ice sheet.


Ice


The melting of mountain glaciers appears to be accelerating, threatening the livelihoods of one fifth or more of the population who depend on glacier ice and seasonal snow for their water supply. For 30 reference glaciers in nine mountain ranges tracked by the World Glacier Monitoring Service, the mean rate of loss since 2000 has roughly doubled since the rate during the previous two decades. Current trends suggest that most glaciers will disappear from the Pyrenees by 2050 and from the mountains of tropical Africa by 2030.


In 2007, summer sea ice in the Arctic Ocean shrank to its smallest extent ever, 24% less than the previous record in 2005, and 34% less than the average minimum extent in the period 1970-2000. In 2008, the minimum ice extent was 9% greater than in 2007, but still the second lowest on record.


Until the summer of 2007, most models projected an ice-free September for the Arctic Ocean towards the end of the current century. Reconsideration based on current trends has led to speculation that this could occur as soon as 2030.


Melting of the Greenland Ice Sheet surface also seems to be accelerating. In the summer of 2007, the rate of melting was some 60% higher than the previous record in 1998.


The loss of ice from West Antarctica is estimated to have increased by 60% in the decade to 2006, and by 140% from the Antarctic Peninsula in the same period.


Recent findings show that warming extends well to the south of the Antarctic Peninsula, to cover most of West Antarctica, an area of warming much larger than previously reported.


The hole in the ozone layer has had a cooling effect on Antarctica, and is partly responsible for masking expected warming on the continent. Recovery of stratospheric ozone, thanks to the phasing out of ozone-depleting substances, is projected to increase Antarctic temperatures in coming decades.


Oceans


Recent estimates of the combined impact of melting land-ice and thermal expansion of the oceans suggest a plausible average sea level rise of between 0.8 and 2.0 metres above the 1990 level by 2100. This compares with a projected rise of between 18 and 59 centimetres in the last IPCC report, which did not include an estimate of large-scale changes in ice-melt rates, due to lack of consensus.


Oceans are becoming more acidic more quickly than expected, jeopardizing the ability of shellfish and corals to form their external skeletons. Water that can corrode a shell-making carbonate substance called aragonite is already welling up during the summer along the California coast, decades earlier than models predict.


Ecosystems


Since the 2007 IPCC report, wide-ranging surveys have shown changes to the seasonal behaviour and distribution of all well-studied marine, freshwater and terrestrial groups of plants and animals. Polar and mountaintop species have seen severe contractions of their ranges.


A recent study projecting the impacts of climate change on the pattern of marine biodiversity suggests dramatic changes to come. Ecosystems in sub-polar waters, the tropics and semi-enclosed seas are predicted to suffer numerous extinctions by 2050, while the Arctic and Southern Oceans will experience severe species invasions. Marine ecosystems as a whole may see a species turnover of up to 60%.



Under the IPCC scenario that most closely matches current trends, i.e., with the highest projected emissions between 12 and 39% of the Earth's land surface could experience previously unknown climate conditions by 2100. A similar proportion, between 10 and 48%, will see existing climates disappear. Many of these "disappearing climates" coincide with biodiversity hotspots, and with the added problem of fragmented habitats and physical obstructions to migration, it is feared many species will struggle to adapt to the new conditions.


Perennial drought conditions have already been observed in South-eastern Australia and South-western North America. Projections suggest that persistent water scarcity will increase in a number of regions in coming years, including southern and northern Africa, the Mediterranean, much of the Middle East, a broad band in Central Asia and the Indian subcontinent.


Management


The reality of a rapidly-changing climate may make conventional approaches to conservation and restoration of habitats ineffective. Drastic measures such as large-scale translocation or assisted colonization of species may need to be considered.


Eco-agriculture, in which landscapes are managed to sustain a range of ecosystem services, including food production, may need to replace the current segregation of land use between conservation and production. This could help create resilient agricultural ecosystems better able to adapt to the changing climate conditions.


Experts increasingly agree that active protection of tropical forests is a cost-effective means of cutting global emissions. An international mechanism of reducing emissions from deforestation and forest degradation (REDD) is likely to emerge as a central component of a new agreement in Copenhagen. However, many issues need to be resolved, such as how to verify the reductions and ensuring fair treatment of local and indigenous forest communities.


A number of innovative approaches are emerging to keep carbon out of the atmosphere, including the use of "biochar," biologically-derived charcoal. It is mixed in soils, increasing fertility and potentially locking up carbon for centuries. This is a 21st century application of a technology known as Terra Preta, or Black Earth, used by Amazon peoples before the arrival of Europeans in South America.
 

To download the full report, visit http://www.unep.org/compendium2009/ 


For more information please contact: 
 
Nick Nuttall, UNEP Spokesperson and Head of Media, on Tel: +254 20 7623084, Mobile: +254 733 632755, or when travelling: +41 795965737, or e-mail: nick.nuttall@unep.org;

Elisabeth Guilbaud-Cox, Senior Communications Officer, UNEP Regional Office for North America, Tel: 1 (202) 974-1307, Mobile: 1 (202) 812-2100, e-mail: elisabeth.guilbaud-cox@unep.org

Link to press release:  http://www.unep.org/Documents.Multilingual/Default.asp?DocumentID=596&ArticleID=6326&l=en

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The Guardian: Met Office warns of catastrophic global warming in our lifetimes

Met Office warns of catastrophic global warming in our lifetimes

• Study says 4 °C rise in temperature could happen by 2060
• Increase could threaten water supply of half world population
Path of global warming
Droughts and heatwaves are predicted to spread if average temperatures rise by 2C. The Met Office's study warns global warming could result in a rise of 4 °C by 2060. Photograph: Vinay Dithajohn/EPA

Unchecked global warming could bring a severe temperature rise of 4 °C within many people's lifetimes, according to a new report for the British government that significantly raises the stakes over climate change.
The study, prepared for the Department of Energy and Climate Change by scientists at the Met Office, challenges the assumption that severe warming will be a threat only for future generations, and warns that a catastrophic 4 °C rise in temperature could happen by 2060 without strong action on emissions.

Officials from 190 countries gather today in Bangkok to continue negotiations on a new deal to tackle global warming, which they aim to secure at United Nations talks in December in Copenhagen.

"We've always talked about these very severe impacts only affecting future generations, but people alive today could live to see a 4 °C rise," said Richard Betts, the head of climate impacts at the Met Office Hadley Centre, who will announce the findings today at a conference at Oxford University. "People will say it's an extreme scenario, and it is an extreme scenario, but it's also a plausible scenario."

According to scientists, a 4 °C rise over pre-industrial levels could threaten the water supply of half the world's population, wipe out up to half of animal and plant species, and swamp low coasts.

A 4 °C average would mask more severe local impacts: the Arctic and western and southern Africa could experience warming up to 10 °C, the Met Office report warns.

The study updates the findings of the 2007 report of the Intergovernmental Panel on Climate Change (IPCC), which said the world would probably warm by 4 °C by 2100 if greenhouse gas emissions continue to rise. The IPCC also listed a more severe scenario, with emissions and temperatures rising further because of more intensive fossil fuel burning, but this was not considered realistic. "That scenario was downplayed because we were more conservative a few years ago. But the way we are going, the most severe scenario is looking more plausible," Betts said.

A report last week from the UN Environment Programme said emissions since 2000 have risen faster than even this IPCC worst-case scenario. "In the 1990s, these scenarios all assumed political will or other phenomena would have brought about the reduction in greenhouse gas emissions by this point. In fact, CO2 emissions from fossil-fuel burning and industrial processes have been accelerating."

The Met Office scientists used new versions of the computer models used to set the IPCC predictions, updated to include so-called carbon feedbacks or tipping points, which occur when warmer temperatures release more carbon, such as from soils.

When they ran the models for the most extreme IPCC scenario, they found that a 4 °C rise could come by 2060 or 2070, depending on the feedbacks. Betts said: "It's important to stress it's not a doomsday scenario, we do have time to stop it happening if we cut greenhouse gas emissions soon." Soaring emissions must peak and start to fall sharply within the next decade to head off a 2 °C rise, he said. To avoid the 4 °C scenario, that peak must come by the 2030s.

A poll of 200 climate experts for the Guardian earlier this year found that most of them expected a temperature rise of 3 °C to 4 °C by the end of the century.

The implications of a 4 °C rise on agriculture, water supplies and wildlife will be discussed at the Oxford conference, which organisers have billed as the first to properly consider such a dramatic scenario.

Mark New, a climate expert at Oxford who has organised the conference, said: "If we get a weak agreement at Copenhagen then there is not just a slight chance of a 4 °C rise, there is a really big chance. It's only in the last five years that scientists have started to realise that 4 °C is becoming increasingly likely and something we need to look at seriously." Limiting global warming to 2 °C could only be achieved with new technology to suck greenhouse gases from the atmosphere. "I think the policy makers know that. I think there is an implicit understanding that they are negotiating not about 2 °C but 3 °C or 5 °C."

Link to article:  http://www.guardian.co.uk/environment/2009/sep/28/met-office-study-global-warming

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V.M. Tiwari, J. Wahr, S. Swensen, GRL 2009: Dwindling groundwater resources in northern India, from satellite gravity observations

Geophysical Research Letters, 36 (2009) L18401; doi: 10.1029/2009GL039401.

Dwindling groundwater resources in northern India, from satellite gravity observations

V. M. Tiwari (National Geophysical Research Institute, CSIR, Hyderabad, India; Department of Physics, University of Colorado, Boulder, CO, U.S.A.), J. Wahr (Department of Physics and Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, U.S.A.), and S. Swenson (Advanced Study Program, National Center for Atmospheric Research, Boulder, CO, U.S.A.)

Received 2 June 2009; accepted 28 July 2009; published 17 September 2009. 

Abstract

Northern India and its surroundings, home to roughly 600 million people, is probably the most heavily irrigated region in the world. Temporal changes in Earth's gravity field in this region as recorded by the GRACE satellite mission, reveal a steady, large-scale mass loss that we attribute to excessive extraction of groundwater. Combining the GRACE data with hydrological models to remove natural variability, we conclude the region lost groundwater at a rate of 54 ± 9 km3/yr between April, 2002 (the start of the GRACE mission) and June, 2008. This is probably the largest rate of groundwater loss in any comparable-sized region on Earth. Its likely contribution to sea level rise is roughly equivalent to that from melting Alaskan glaciers. This trend, if sustained, will lead to a major water crisis in this region when this non-renewable resource is exhausted.

Tiwari, V. M., J. Wahr, & S. Swenson (2009), Dwindling groundwater resources in northern India, from satellite gravity observations, Geophys. Res. Lett., 36, L18401; doi: 10.1029/2009GL039401.

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Steiner, Kirchengas, Lackner, Pirscher, Borsche, Foelsche, GRL 2009, Atmospheric temperature change detection with GPS radio occultation 1995-2008

Geophysical Research Letters, 36 (2009)  L18702; doi: 10.1029/2009GL039777.

Atmospheric temperature change detection with GPS radio occultation 1995 to 2008

A. K. Steiner, G. Kirchengas, B. C. Lackner, B. Pirscher, M. Borsche, and U. Foelsche (Wegener Center for Climate and Global Change and Institute for Geophysics, Astrophysics, and Meteorology, University of Graz, Graz, Austria)

Received 26 June 2009; accepted 26 August 2009; published 22 September 2009. 

Abstract

Existing upper air records of radiosonde and operational satellite data recently showed a reconciliation of temperature trends but structural uncertainties remain. GPS radio occultation (RO) provides a new high-quality record, profiling the upper troposphere and lower stratosphere with stability and homogeneity. Here we show that climate trends are since recently detected by RO data, consistent with earliest detection times estimated by simulations. Based on a temperature change detection study using the RO record within 1995–2008 we found a significant cooling trend in the tropical lower stratosphere in February while in the upper troposphere an emerging warming trend is obscured by El Niño variability. The observed trends and warming/cooling contrast across the tropopause agree well with radiosonde data and basically with climate model simulations, the latter tentatively showing less contrast. The performance of the short RO record to date underpins its capability to become a climate benchmark record in the future.

Steiner, A. K., G. Kirchengast, B. C. Lackner, B. Pirscher, M. Borsche & U. Foelsche (2009), Atmospheric temperature change detection with GPS radio occultation 1995 to 2008, Geophys. Res. Lett., 36, L18702; doi: 10.1029/2009GL039777.

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H. Douville, GRL (2009), Stratospheric polar vortex influence on Northern Hemisphere winter climate variability

Geophysical Research Letters, 36 (2009) L18703; doi: 10.1029/2009GL039334.

Stratospheric polar vortex influence on Northern Hemisphere winter climate variability

H. Douville (CNRM, GAME, Météo-France, CNRS, Toulouse, France)

Received 8 June 2009; accepted 18 August 2009; published 23 September 2009.

Abstract

Given the low skill of seasonal forecasts in the Northern Hemisphere, it is important to look for extra sources of long-range predictability in addition to the global distribution of sea surface temperature (SST). Former studies have suggested the potential contribution of the stratosphere but have never really quantified this influence and compared it to the SST forcing. In the present study, two ensembles of global atmospheric simulations driven by observed SST and radiative forcings have been performed over the 1971–2000 period. In the perturbed experiment, the stratospheric dynamics and temperature is nudged towards the ERA40 reanalyses north of 25°N in order to mimic a “perfect” polar vortex. The comparison with the control experiment reveals a strong improvement in the simulation of the Arctic and North Atlantic Oscillation, with obvious positive impacts on the interannual variability of winter surface air temperature and precipitation, especially over Europe.

Douville, H. (2009), Stratospheric polar vortex influence on Northern Hemisphere winter climate variability, Geophys. Res. Lett., 36, L18703; doi: 10.1029/2009GL039334.

Link to abstract:  http://www.agu.org/pubs/crossref/2009/2009GL039334.shtml

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Marco Tedesco & Andrew J. Monaghan, GRL (2009): An updated Antarctic melt record through 2009 and its linkages to high-latitude and tropical climate variability

Geophysical Research Letters, 36 (2009) L18502; doi: 10.1029/2009GL039186.

An updated Antarctic melt record through 2009 and its linkages to high-latitude and tropical climate variability

Marco Tedesco (Earth and Atmospheric Sciences, City College of New York, New York, NY, U.S.A.) and Andrew J. Monaghan (National Center for Atmospheric Research, Boulder, CO, U.S.A.)

Received 13 May 2009; accepted 12 August 2009; published 24 September 2009. 

Abstract

A 30-year minimum Antarctic snowmelt record occurred during austral summer 2008–2009 according to spaceborne microwave observations for 1980–2009. Strong positive phases of both the El-Niño Southern Oscillation (ENSO) and the Southern Hemisphere Annular Mode (SAM) were recorded during the months leading up to and including the 2008–2009 melt season. The 30-year record confirms that significant negative correlations exist at regional and continental scales between austral summer melting and both the ENSO and SAM indices for October–January. In particular, the strongest negative melting anomalies (such as those in 2008 and 2009) are related to amplified large-scale atmospheric forcing when both the SAM and ENSO are in positive phases. Our results suggest that enhanced snowmelt is likely to occur if recent positive summer SAM trends subside in conjunction with the projected recovery of stratospheric ozone levels, with subsequent impacts on ice sheet mass balance and sea level trends.

Tedesco, M., & A. J. Monaghan (2009), An updated Antarctic melt record through 2009 and its linkages to high-latitude and tropical climate variability, Geophys. Res. Lett., 36, L18502; doi: 10.1029/2009GL039186.

Link to abstract:  http://www.agu.org/pubs/crossref/2009/2009GL039186.shtml

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Dlugokencky et al., GRL (September 2009): Observational constraints on recent increases in the atmospheric CH4 burden

Geophysical Research Letters, 36 (2009) L18803; doi: 10.1029/2009GL039780.

Observational constraints on recent increases in the atmospheric CH4 burden 

 E. J. Dlugokencky, L. Bruhwiler (NOAA Earth System Research Laboratory, Boulder, CO, U.S.A.), J. W. C. White (INSTAAR, University of Colorado, Boulder, CO, U.S.A.), L. K. Emmons (National Center for Atmospheric Research, Boulder, CO, U.S.A.), P. C. Novelli, S. A. Montzka, K. A. Masarie, P. M. Lang, A. M. Crotwell, J. B. Miller (NOAA Earth System Research Laboratory, Boulder, CO, U.S.A.) and L. V. Gatti (Divisao de Quimica Ambiental, Laboratorio de Quimica Atmosferica, Insituto de Pesquisas Energéticas e Nucleares, São Paulo, Brazil )

Received 6 July 2009; accepted 18 August 2009; published 17 September 2009. 

Abstract

Measurements of atmospheric CH4 from air samples collected weekly at 46 remote surface sites show that, after a decade of near-zero growth, globally averaged atmospheric methane increased during 2007 and 2008. During 2007, CH4 increased by 8.3 ± 0.6 ppb. CH4 mole fractions averaged over polar northern latitudes and the Southern Hemisphere increased more than other zonally averaged regions. In 2008, globally averaged CH4 increased by 4.4 ± 0.6 ppb; the largest increase was in the tropics, while polar northern latitudes did not increase. Satellite and in situ CO observations suggest only a minor contribution to increased CH4 from biomass burning. The most likely drivers of the CH4 anomalies observed during 2007 and 2008 are anomalously high temperatures in the Arctic and greater than average precipitation in the tropics. Near-zero CH4 growth in the Arctic during 2008 suggests we have not yet activated strong climate feedbacks from permafrost and CH4 hydrates.

Dlugokencky, E. J., et al. (2009), Observational constraints on recent increases in the atmospheric CH4 burden, Geophys. Res. Lett., 36, L18803; doi: 10.1029/2009GL039780.

Link to abstract:  http://www.agu.org/pubs/crossref/2009/2009GL039780.shtml

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NOAA: Unusual Arctic warmth, tropical wetness likely cause for methane increase, E. Dlugokencky et al., GRL

Unusual Arctic warmth, tropical wetness likely cause for methane increase

NOAA, September 25, 2009
Wetlands at the Parker River restoration site.

Wetlands at the Parker River restoration site. High resolution (Credit: NOAA)

Unusually high temperatures in the Arctic and heavy rains in the tropics likely drove a global increase in atmospheric methane in 2007 and 2008 after a decade of near-zero growth, according to a new study. Methane is the second most abundant greenhouse gas after carbon dioxide, albeit a distant second.

NOAA scientists and their colleagues analyzed measurements from 1983 to 2008 from air samples collected weekly at 46 surface locations around the world. Their findings will appear in the September 28 print edition of the American Geophysical Union’s Geophysical Research Letters and are available online now.

“At least three factors likely contributed to the methane increase,” said Ed Dlugokencky, a methane expert at NOAA’s Earth System Research Laboratory in Boulder, Colo. “It was very warm in the Arctic, there was some tropical forest burning, and there was increased rain in Indonesia and the Amazon.”

In the tropics, the scientists note, the increased rainfall resulted in longer periods of rainfall and larger wetland areas, allowing microbes to produce more methane. Starting in mid-2007, scientists noticed La Niña conditions beginning, waning and then intensifying in early 2008. This kind of climate condition typically brings wetter-than-normal conditions in some tropical regions and cooler sea surface temperatures in the central and eastern tropical Pacific Ocean. It can persist for as long as two years. In the United States, La Niña often signals drier-than-normal conditions in the Southwest and Central Plains regions, and wetter fall and winter seasons in the Pacific Northwest.

Observations from satellites and ground sites suggest that biomass burning – the burning of plant and other organic material that releases carbon dioxide and methane – contributed about 20% of the total methane released into the atmosphere in 2007.
A magnificent view of wetlands and tidal streams in the Ashe Island area.

A magnificent view of wetlands and tidal streams in the Ashe Island area. High resolution (Credit: NOAA)

However, during the scientists’ 2007 measurement of methane for northern wetland regions, including the Arctic, temperatures for the year were the warmest on record. This temperature increase coincided with the large jump in the amount of methane measured in that area.

Dlugokencky and his colleagues from the United States and Brazil note that while climate change can trigger a process which converts trapped carbon in permafrost to methane, as well as release methane embedded in Arctic hydrates – a compound formed with water - their observations “are not consistent with sustained changes there yet.”

Methane is typically created in oxygen-deprived environments, such as flooded wetlands, peat bogs, rice paddies, landfills, termite colonies, and the digestive tracts of cows and other ruminant animals. The gas also escapes during fossil fuel extraction and distribution and is emitted during fires.

Authors of the study are: E. Dlugokencky, L. Bruhwiler, P.C. Novelli, S. A. Montzka, K. A. Masarie, P. M. Lang, A.M. Crotwell, and J.B. Miller of NOAA’s Earth System Research Laboratory, Boulder, Colo.; J.W.C. White of the Institute of Arctic and Alpine Research, University of Colorado, Boulder, Colo.; L. K. Emmons of the National Center for Atmospheric Research, Boulder, Colo.; and L.V. Gatti of the Laboratorio de Quimica Atmosferica, Instituto de Pesquisas Energéticas e Nucleares, São Paulo, Brazil. Crotwell and Miller are also at the Cooperative Institute for Research in Environmental Sciences in Boulder, Colo. The paper is available online.

NOAA understands and predicts changes in the Earth's environment, from the depths of the ocean to the surface of the sun, and conserves and manages our coastal and marine resources.

Link:  http://www.noaanews.noaa.gov/stories2009/20090925_arctic.html

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Jordan to Desalinate Red Sea Water in Dead Sea


This report is none too clear, but the gist of the plan is to operate a desalination plant on the Red sea or even uphill near the Dead Sea. A byproduct of desalination happens to be concentrated brine usually equal to a third or so of the through put. In the gulf this brine is put back into the sea as conveniently as possible.



In this particular case we are pumping the sea water somewhat up hill to the Dead Sea and then running it all through a turbine to produce power sufficient to pay for the pumping and perhaps even all the energy cost of the desalination itself. If it can be made to work that efficiently, then it is a given that this is one of many such plants and that the Dead Sea will be slowly recharged.



The only limit then will be the ability of the Dead Sea to absorb brine, and since surface area expands as it fills, it is quite a lot larger than simple calculations would likely suggest.



We can certainly take it back to historical levels and even a great deal higher since it was once much fuller.



The natural high grade brines will sit under the layer of new brines and be pumped out as needed for industrial purposes. This is a small inconvenience.



Jordan to go solo with Red Sea to Dead Sea pipeline



http://www.terradaily.com/images/red-sea-dead-sea-pipeline-bg.jpg




The plan is for the pipeline to draw off 310 million cubic metres (10.5 billion cubic feet) of water each year, of which 240 million will be fed into the desalination plant at the Jordanian Red Sea port of Aqaba, enabling an annual production of 120 million cubic metres of drinking water.




by Staff Writers



Amman (AFP) Sept 27, 2009



http://www.terradaily.com/reports/Jordan_to_go_solo_with_Red_Sea_to_Dead_Sea_pipeline_999.html




Jordan has decided to go it alone and build a two-billion-dollar pipeline from the Red Sea to the Dead Sea without help from proposed partners Israel and the Palestinian Authority, an official told AFP.


"Jordan is thirsty and cannot wait any longer," said Fayez Batayneh, the country's chief representative in the mega-project to provide drinking water and begin refilling the Dead Sea, which is on course to dry out by 2050.


"Israel and the Palestinians have raised no objection to Jordan starting on the first phase by itself," Batayneh said.


"The first stage, at an estimated cost of two billion dollars, will begin in 2010 and should be completed in 2014 on a BOT (build, operate, transfer) basis," he said.


The plan is for the pipeline to draw off 310 million cubic metres (10.5 billion cubic feet) of water each year, of which 240 million will be fed into the desalination plant at the Jordanian Red Sea port of Aqaba, enabling an annual production of 120 million cubic metres of drinking water.


Batayneh said the remaining 190 million cubic metres will be channelled towards the Dead Sea, the saltiest natural lake on the planet and the lowest point on the earth's surface.


Jordan, where the population of six million people is expanding by 3.5 percent a year, is recognised as one of the 10 driest countries in the world, with desert covering 92 percent of its territory.


The kingdom relies mainly on winter rain for its water needs, which are projected to reach 1.6 billion cubic metres in 2015.


Israel, the Palestinian Authority and Jordan agreed in 2005 on the outlines of a project to channel two billion cubic metres of water a year via a 200-hilometre (120-mile) canal in order to restore the level of the Dead Sea, produce fresh water and generate electricity.


The total cost of the scheme has been estimated at 11 billion dollars.


Written by fatih al-farahat in , ,


Hockey Stick Fraud


There is no way to be generous or to dodge this bullet. We now have outright confirmation that the data was deliberately selected to provide the dramatic eye catching result that was made it so famous. This is not science so much as a publicist’s dodgy manipulation of data to support a doubtful scheme.


I am certain every scientist has faced the frustration of months of hard work merely showing no evidence for the proposed theory. Once again our scientists had no evidence. So they merely selected the best data points in a statistical distribution and discarded the rest. I can prove anything if I am allowed to do that. Hell, I know of this great gold mine in which the grades exceed five ounces to the ton. – see this assay sheet?


When these guys floated their paper, they had no expectation anyone else would care and result were important in order to push their spurious claims. Then the world paid attention and they hid the data for ten years so no one could discover what they had done.


That is now over and we now left with a paper that manipulated the data in several places and actually fabricated the hockey stick upswing. It does not get any worse than this and on top of that it has been poisoning the debate for a decade instead of been called to account immediately.


In fact, why did the referees not ask for the raw data they relied on? That chart was simply too good to be true and everyone was lazy. I know that I thought it suspect the first time I laid eyes on it. But then after years of reviewing assay results, I am a little more demanding perhaps and appreciative how difficult it is to get good data at all.



Monday, September 28, 2009


http://planetgore.nationalreview.com/post/?q=Y2Q5ZGExZTc3ZTlmMTA5OTdhOGRjNzdlNmU4N2M4ZTg


Mann-made Warming Confirmed [Chris Horner]


It turns out that trees can scream.



A colleague in the climate-realist blogosphere sends along the following narrative which all Planet Gore readers, even the muttering monitors over at Team Soros, should find very interesting. The inescapable and powerful conclusion is that Mann-made warming is real, while man-made warming remains at best a theory, more likely a hypothesis. Really.


This story deserves to be told.




1: In 1998, a paper is published by Dr. Michael Mann, then at the University of Virginia, now a Penn State climatologist, and co-authors Bradley and Hughes. The paper is named: Northern Hemisphere Temperatures During the Past Millennium: Inferences, Uncertainties, and Limitations. The paper becomes known as MBH98.



The conclusion of tree ring reconstruction of climate for the past 1,000 years is that we are now in the hottest period in modern history, ever.




See the graph http://www.ncdc.noaa.gov/paleo/image/mann/manna_99.gif




Steve McIntyre, a Canadian mathematician in Toronto, suspects tree rings aren't telling a valid story with that giant uptick at the right side of the graph, implicating the 20th century as the "hottest period in 1000 years," which alarmists latch onto as proof of AGW. The graph is dubbed the "Hockey Stick" and becomes famous worldwide. Al Gore uses it in his movie An Inconvenient Truth in the famous "elevator scene."




2: Steve attempts to replicate Michael Mann's tree ring work in the paper MBH98, but is stymied by lack of data archiving. He sends dozens of letters over the years trying to get access to data but access is denied. McIntyre and Ross McKitrick, of the University of Guelph publish a paper in 2004 criticizing the work. A new website is formed in 2004 called Real Climate, by the people who put together the tree ring data and they denounce the scientific criticism:




http://www.realclimate.org/index.php/archives/2004/12/false-claims-by-mcintyre-and-mckitrick-regarding-the-mann-et-al-1998reconstruction/

3: Years go by.McIntyre is still stymied trying to get access to the original source data so that he can replicate the Mann 1998 conclusion. In 2008 Mann publishes another paper in bolstering his tree ring claim due to all of the controversy surrounding it. A Mann co-author and source of tree ring data (Professor Keith Briffa of the Hadley UK Climate Research Unit) used one of the tree ring data series (Yamal in Russia) in a paper published in the Philosophical Transactions of the Royal Society in 2008, which has a strict data archiving policy. Thanks to that policy, Steve McIntyre fought and won access to that data just last week.




4: Having the Yamal data in complete form, McIntyre replicates it, and discovers that one of Mann's co-authors, Briffa, had cherry picked 10 tree data sets out of a much larger set of trees sampled in Yamal.




5: When all of the tree ring data from Yamal is plotted, the famous hockey stick disappears. Not only does it disappear, but goes negative. The conclusion is inescapable. The tree ring data was hand-picked to get the desired result.




These are the relevant graphs from McIntyre showing what the newly available data demonstrates.



http://www.climateaudit.org/wp-content/uploads/2009/09/rcs_chronologies1.gif

http://www.climateaudit.org/wp-content/uploads/2009/09/rcs_merged.gif”



So now the question is, if tree rings scream and their message is one that few want to hear, does their message get heard?


Written by fatih al-farahat in , ,


Cancer Biossenser Development



This is a pleasant surprise that leaps us forward to the day when cancer is cured. It is well known that early detection allows us to aggressively eliminate the disease while it is still easy to treat.


I recall that in the first applications of the AIDS cocktail that the dosages were aggressive and caused severe side effects. Today the process is almost gentle and victims are living out their lives in very good order.


We have the ability to do this with the early onset stages of almost all cancers, yet the care is dominated by late cancers and desperate interventions. So a device able to screen immediately for the presence of offending cell forms will swiftly change all that.


And intervention is likely to be a cocktail of specific drugs able to suppress the problem, or location and removal if warranted.


It also sounds like it will be available rather quickly and can become as ubiquous as a stethoscope.


This also technology that will see steady upgrading similar to what we have experienced with cell phones.


September 28, 2009


U of T researchers create microchip that can detect type and severity of cancer


http://nextbigfuture.com/2009/09/u-of-t-researchers-create-microchip.html


https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjBcRel-c6URicMOJg__kbEsLyai70m0UbyO78IgZtuREaQLc7XOIZjogv7CDoB7pjGjZuByiqZYFWKn8scf1kc3bgUL5Q_bmipl4e-joUqofVQrOft2yDI7zNugV2PhAdf74Zl9oGbIys/s1600-h/cancerdiagcanada.jpg



University of Toronto researchers, Shana Kelley and Ted Sargent, have made a cancer diagnostic breakthrough. Kelley said a five-year time frame would be a "conservative estimate" to get the device on the market.


U of T researchers have used nanomaterials to develop an inexpensive microchip sensitive enough to quickly determine the type and severity of a patient's cancer so that the disease can be detected earlier for more effective treatment.



The researchers' new device can easily sense the signature biomarkers that indicate the presence of cancer at the cellular level, even though these biomolecules - genes that indicate aggressive or benign forms of the disease and differentiate subtypes of the cancer - are generally present only at low levels in biological samples. Analysis can be completed in 30 minutes, a vast improvement over the existing diagnostic procedures that generally take days.



"Today, it takes a room filled with computers to evaluate a clinically relevant sample of cancer biomarkers and the results aren't quickly available," said Shana Kelley, a professor in the Leslie Dan Faculty of Pharmacy and the Faculty of Medicine, who was a lead investigator on the project and a co-author on the publication.



"Our team was able to measure biomolecules on an electronic chip the size of your fingertip and analyse the sample within half an hour. The instrumentation required for this analysis can be contained within a unit the size of a BlackBerry."

Kelley, along with engineering professor Ted Sargent - a fellow lead investigator and U of T's Canada Research Chair in Nanotechnology - and an interdisciplinary team from Princess Margaret Hospital and Queen's University, found that conventional, flat metal electrical sensors were inadequate to sense cancer’s particular biomarkers. Instead, they designed and fabricated a chip and decorated it with nanometre-sized wires and molecular "bait."




Abstract Nature Nanotechnology: Programming the detection limits of biosensors through controlled nanostructuring


Advances in materials chemistry offer a range of nanostructured shapes and textures for building new biosensors. Previous reports have implied that controlling the properties of sensor substrates can improve detection sensitivities, but the evidence remains indirect. Here we show that by nanostructuring the sensing electrodes, it is possible to create nucleic acid sensors that have a broad range of sensitivities and that are capable of rapid analysis. Only highly branched electrodes with fine structuring attained attomolar sensitivity. Nucleic acid probes immobilized on finely nanostructured electrodes appear more accessible and therefore complex more rapidly with target molecules in solution. By forming arrays of microelectrodes with different degrees of nanostructuring, we expanded the dynamic range of a sensor system from two to six orders of magnitude. The demonstration of an intimate link between nanoscale sensor structure and biodetection sensitivity will aid the development of high performance diagnostic tools for biology and medicine.




2 page pdf with supplemental information



Shana Kelly Lab webpage at the University of Toronto


"Uniting DNA - the molecule of life - with speedy, miniaturized electronic chips is an example of cross-disciplinary convergence," said Sargent. "By working with outstanding researchers in nanomaterials, pharmaceutical sciences, and electrical engineering, we were able to demonstrate that controlled integration of nanomaterials provides a major advantage in disease detection and analysis."




The speed and accuracy provided by their device is welcome news to cancer researchers.




The team's microchip platform has been tested on prostate cancer, as described in a paper published in ACS Nano, and head and neck cancer models. It could potentially be used to diagnose and assess other cancers, as well as infectious diseases such as HIV, MRSA and H1N1 flu.




"The system developed by the Kelley/Sargent team is a revolutionary technology that could allow us to track biomarkers that might have significant relevance to cancer, with a combination of speed, sensitivity, and accuracy not available with any current technology," said Dr. Fei-Fei Liu, a radiation oncologist at Princess Margaret Hospital and Head of Applied Molecular Oncology Division, Ontario Cancer Institute. "This type of approach could have a profound impact on the future management for our cancer patients."

Written by fatih al-farahat in ,


TWC: Bird's eye view of the North Pole and how the weakening of the polar vortex is allowing not so good things to go on weatherwise

OK, readers, that was a really silly title, I know.

But, I don't know how else to state it. Please click on the image to enlarge it. If you look carefully at the clouds, you can see that France is dry and so is the entire western half of the U.S.

If the polar vortex is too weak to keep the warm air currents far enough south, then they keep going north.

Sure, sometimes the west is dry and so is France, but I just thought this was a nice image to demonstrate what is likely to be a more dominant weather pattern when the Arctic warms up.




Blogger Enno said...
heh that was funny! but -- "what is likely to be a more dominant weather pattern" ...can you state or link to some substantiation why/how one knows that this specific pattern is likely to be more dominant? Thank you for your blog, generally.
September 29, 2009 3:14 PM
Delete
Blogger Tenney Naumer said...
Dear Enno,Thanks for your comment!For substantiation, please click on the relevant labels, e.g., "storm tracks...," polar vortex, and other related labels.There is plenty of research being done on these things, and whenever I run across it, I make a point to post it to the blog.Best regards,Tenney
September 30, 2009 8:47 AM

Written by fatih al-farahat in


Joseph Romm: Met Office: Catastrophic climate change, 13-18 °F over most of U.S. and 27 °F in the Arctic, could happen in 50 years, but “we do have time to stop it if we cut greenhouse gas emissions soon”


UK Met Office: Catastrophic climate change, 13-18 °F over most of U.S. and 27 °F in the Arctic, could happen in 50 years, but “we do have time to stop it if we cut greenhouse gas emissions soon”

 by Joseph Romm, Climate Progress, September 28, 2009 
 
Finally, some of the top climate modelers in the world have done a “plausible worst case scenario,” as Dr Richard Betts, Head of Climate Impacts at the Met Office Hadley Centre, put it today in a terrific and terrifying talk (audio here, PPT here).

No, I’m not taking about a simple analysis of what happens if the nation and the world just keep on our current emissions path.  We’ve known that end-of-century catastrophe for a while (see “M.I.T. doubles its 2095 warming projection to 10 °F — with 866 ppm and Arctic warming of 20 °F").  I’m talking about running a high emissions scenario (i.e., business as usual) in one of the few global climate models capable of analyzing strong carbon cycle feedbacks.  This is what you get [temperature in degrees Celsius, multiple by 1.8 for Fahrenheit]:
Graphic of chnage in temperature
The key point is that while this warming occurs between 1961-1990 and 2090-2099 for the high-end scenarios without carbon cycle feedbacks, in about 10% of Hadley’s model runs with the feedbacks, it occurs around 2060.  Betts calls that the “plausible worst case scenario.”  It is something the IPCC and the rest of the scientific community should have laid out a long time ago.

As the Met Office notes here, “In some areas warming could be significantly higher (10 °C = 15 °F) or more)”:

  • The Arctic could warm by up to 15.2 °C (27.4 °F) for a high-emissions scenario, enhanced by melting of snow and ice causing more of the Sun’s radiation to be absorbed.
  • For Africa, the western and southern regions are expected to experience both large warming (up to 10 °C (18 °F)) and drying.
  • Some land areas could warm by 7 °C (12.6 °F) or more.
  • Rainfall could decrease by 20% or more in some areas, although there is a spread in the magnitude of drying. All computer models indicate reductions in rainfall over western and southern Africa, Central America, the Mediterranean and parts of coastal Australia.
  • In other areas, such as India, rainfall could increase by 20% or more. Higher rainfall increases the risk of river flooding.
Large parts of the inland United States would warm by 15-18 °F, even worse than the NOAA-led 13-agency impacts report found “Our hellish future: Definitive NOAA-led report on U.S. climate impacts warns of scorching 9-11 °F warming over most of inland U.S. by 2090 with Kansas above 90 °F some 120 days a year — and that isn’t the worst case, it’s business as usual!”
Dr Betts added: “Together these impacts will have very large consequences for food security, water availability and health. However, it is possible to avoid these dangerous levels of temperature rise by cutting greenhouse gas emissions. If global emissions peak within the next decade and then decrease rapidly it may be possible to avoid at least half of the four degrees of warming.”
A DECC spokesman said: “This report illustrates why it is imperative for the world to reach an ambitious climate deal at Copenhagen which keeps the global temperature increase to below two degrees.”
Betts “presented the new findings at a special conference” today.  “4 degrees and beyond at Oxford University, attended by 130 international scientists and policy specialists, is the first to consider the global consequences of climate change beyond 2 °C.”  You can find all the talks here.

The UK Telegraph story is here.  The Guardian story is “Met Office warns of catastrophic global warming in our lifetimes:  Study says 4 °C rise in temperature could happen by 2060, Increase could threaten water supply of half world population”:
When they ran the models for the most extreme IPCC scenario, they found that a 4 °C rise could come by 2060 or 2070, depending on the feedbacks. Betts said: “It’s important to stress it’s not a doomsday scenario, we do have time to stop it happening if we cut greenhouse gas emissions soon.” Soaring emissions must peak and start to fall sharply within the next decade to head off a 2 °C rise, he said. To avoid the 4 °C scenario, that peak must come by the 2030s.
Again, this is not the likely impact for 2060 if we fail to act aggressively, but it is a plausible worst-case scenario that should invalidate all economic cost-benefit analysis done to date.

Kudos to Betts and the Met Office for this important, uncharacteristically blunt, and long-overdue analysis.

Link:  http://climateprogress.org/2009/09/28/uk-met-office-catastrophic-climate-change-could-happen-with-50-years/

Written by fatih al-farahat in , ,


Bronze Age Climate Restoration



Those who followed my blog last year saw me work at tracking and isolating the various likely factors responsible for the temperature variation experienced throughout the ten thousand year Holocene. A big question mark was the existence of a two thousand year or more Bronze Age optimum that ended with the Hekla event in 1159BCE. We ran down a lot of factors and in fairness none appeared up to the task of explaining that particular optimum.



Since then, the climate has precipitously cooled and then warmed slowly over decades approaching the former optimum but actually coming nowhere close. The Rhine has been frozen several times throughout history and each time local climate took a long time to recover.



Yesterday’s item finally provides a creditable mechanism to operate this engine.



We have a layer of freshened water that is between one to two hundred meters thick lying on top of the underlying ocean waters. The temperature of these underlying waters is about two degrees over the freezing point of fresh water ice. That is a huge supply of available heat that if actually mixed with the overlying ice would eliminate it.



The upper layer is a degree or so below the freezing point. This means that a sustained warm spell and plenty of help from winds could remove this layer. If this layer is removed, it becomes decidedly harder for sea ice to form at all and its breakup the next summer will simply put it back to the way it was.



With surface temperatures a couple of degrees above freezing during the summer, the land will warm up and as happened during the Bronze Age, the permafrost will disappear.



It is pretty obvious that the Hekla event gave twenty years without crops and that means the gain of at least a couple of meters of sea ice each of those years. Over twenty years that likely added up to a beginning round of forty meters. The process likely continued at a slower pace for centuries longer until the sea ice approached a thickness of even a hundred meters or more.



What happens with sea ice is that as it ages the salt is slowly removed and this salt mixes into the surrounding ocean were normal circulation takes it eventually out into the Atlantic.



Thus the post Bronze Age cold spell produced a fresh water layer sitting directly on top of the polar sea. The lack of severe storms failed to produce any mixing since it was way too thick anyway.



The present situation and some fortuitous winds appear to have thinned this layer and have led to the present gross reduction in sea ice thickness. I do not think that the remaining sea ice is any more than part of a two year cycle of ice passing through the gyre and if not that yet, is about to be.



The big question now is whether the winds or normal seasonal warming, sufficient to remove this fresh water cap anytime soon. We are at the point in which it can do a lot of good. Yet I am aware we have been here before for decades even only to have it abruptly end.



And that mechanism is now a little clearer. For some reason we get a summer or two without any melting and suddenly we have a lot of ice. One Alaskan Volcano could do that. It really is that quick. If this mass of left over freshened water from Hekla could be eliminated though, we could return to Bronze Age conditions.