Heaven and Science

Without doubt, reports of near death recollections have excited folks looking for a glimpse of a afterlife for the human soul.  The idea of the immortal soul is imbedded deeply in the mythos of our culture and is accepted by most.  It has been tied up with a wide range of religious teachings that contributed nothing to our understanding.  The soul is the living active memory of our lives.  We can comprehend that idea.

Today, we can comprehend the idea that such a materially defined soul could be mapped onto a physical device to provide a form of immortality or at least longevity for the soul.

It is not a big leap from that idea to taking on the challenge and creating that capacity ourselves.  There are plenty of reasons that prohibit us from doing it now, but they are exactly the type of difficulties that science tackles and overcomes.

The creditable idea is that science will allow us to preserve the human soul as defined above.  It is creditable that living human beings will one day be able to automatically record their lives.

I can take this further for if you wish to go back and read my appropriate posts you will discover that I have conjectured that mankind has already completed techno development back before the end of the ice age whose end they triggered.  They had transitioned into space adapted humanity with long lives and then exited to space habitats using large magnetic exclusion ships.  After the Earth settled down, they recolonized Earth with a number of settler populations whose lives were naturally short.  We are the descendents.

It makes complete sense to record those lives and restore them to donors if possible.  No data is ever lost and it becomes possible to attract volunteers to the task at hand which happens to be terraforming the Earth to accept huge populations.  This job is well underway.  It is humanities primary mission.  Of course, it would be better to not tell us anything.

All of a sudden heaven merely becomes a real place in which we resume our lives as space adapted humans, perhaps until we take another tour of duty.

My point is that I can construct a paradigm for heaven and God that once again conforms rather nicely to our only sources, while stripping out the overlay of mystery.  It certainly were science is taking us and the only oddity is that we passed this way before.

Can Science Explain Heaven?

Scientists try to explain near-death experiences.

By Lisa Miller | Newsweek Web Exclusive

Mar 26, 2010

http://www.newsweek.com/id/235462

There are those who believe that science will eventually explain everything—including our enduring belief in heaven. The thesis here is very simple: heaven is not a real place, or even a process or a supernatural event. It's something that happens in your brain as you die.

I first encountered this idea as I was researching my new book, Heaven: Our Enduring Fascination With the Afterlife. I was having lunch with my friend and colleague Christopher Dickey, who told me that his father, the writer James Dickey, had a fantasy of heaven in which all of his closest friends were sitting around a swimming pool, chatting. "There was nothing special about the pool itself," wrote Chris in Summer of Deliverance: A Memoir of Father and Son. "Nobody walked on the water. And he never told me who the friends were ... But what he took away from the dream was a sense of contentment, of being at ease with himself and the world, as if he had gotten a preview of heaven. He called that place 'The Happy Swimming Pool.' " Chris believes that everything we think we know about heaven happens in the moments before death. After that, there's nothing.

Science cannot definitively proof or disprove Chris's theory, but some scientists are willing to take guesses. And these guesses are based, in part, on a growing body of research around near-death experience (NDE). According to a 2000 article in The Lancet, between 9 and 18 percent of people who have been demonstrably near death report having had such an experience. And surveys of NDE accounts show great similarities in the details. People who have had NDEs describe—like some religious visionaries—a tunnel, a light, a gate, or a door, a sense of being out of the body, meeting people they know or have heard about, finding themselves in the presence of God, and then returning, changed.

Andrew Newberg is an associate professor in the radiology department at the University of Pennsylvania who has made his reputation studying the brain scans of religious people (nuns and monks) who have ecstatic experiences as they meditate. He believes the "tunnel" and "light" phenomena can be explained easily. As your eyesight fades, you lose the peripheral areas first, he hypothesizes. "That's why you'd have a tunnel sensation." If you see a bright light, that could be the central part of the visual system shutting down last.

Newberg puts forward the following scenario, which, he emphasizes, is guesswork. When people die, two parts of the brain, which usually work in opposition to each other, act cooperatively. The sympathetic nervous system—a web of nerves and neurons running through the spinal cord and spread to virtually every organ in the body—is responsible for arousal and excitement. It gets you ready for action. The parasympathetic system—with which the sympathetic system is entwined—calms you down and rejuvenates you. In life, the turning on of one system prompts the shutting down of the other. The sympathetic nervous system kicks in when a car cuts you off on the highway; the parasympathetic system is in charge as you're falling asleep. But in the brains of people reporting mystical experiences—and, perhaps, in death—both systems are fully "on," giving a person the sensation both of slowing down, being "out of body," and of seeing things vividly, including memories of important people and past events. Does Newberg believe, then, that visions of heaven are merely chemical-neurological events? He laughs nervously. "I don't know." He laughs again. "It's, um … I don't think we have enough evidence to say."

Since at least the 1980s, scientists have theorized that NDEs occur as a kind of physiological self-defense mechanism. In order to guard against damage during trauma, the brain releases protective chemicals that also happen to trigger intense hallucinations. This theory gained traction after scientists realized that virtually all the features of an NDE—a sense of moving through a tunnel, and "out of body" feeling, spiritual awe, visual hallucinations, and intense memories—can be reproduced with a stiff dose of ketamine, a horse tranquilizer frequently used as a party drug. In 2000, a psychiatrist named Karl Jansen wrote a book, Ketamine: Dreams and Realities, in which he interviewed a number of recreational users. One of them, who called himself K.U., describes one of his drug trips this way: "I came out into a golden Light. I rose into the Light and found myself having an unspoken interchange with the Light, which I believed to be God." Dante said it better, but the vision is astonishingly the same.

Adapted from the forthcoming book Heaven: Our Enduring Fascination With the Afterlifeby Lisa Miller. To be published by Harper, an imprint of HarperCollins. Copyright ©2010 by Lisa Miller. Reprinted by arrangement with the author.

Global Agriculture Needs Radical Change

I grow weary of these reports bemoaning the so called lack of progress in global agriculture.  As I have posted many times we need to do two simple things.  The first is that we need to empower the land operator himself everywhere.  The farmer needs to own or have a reasonable expectation of owning his land and in the process have access to cost effective credit.  No and no less is demanded.  That individual is the single most productive method of working the land.

If large landowners think that this is unreasonable then tax their land on the basis of the gross income earned by the most efficient small operator.  Why should the government give up revenue?

Then actively support any and all biochar protocols to steadily eliminate the need for chemical fertilizer.  The method has been field tested for centuries without any aid from modern tools.  Surely every farmer can sort out some way to produce enough.  In fact, that is exactly what is presently taking place in some locales in Africa.

The radical change will be the onset of the biochar revolution.

Radical Change Needed For Global Agriculture

by Staff Writers

London, UK (SPX) Mar 30, 2010

According to the report, the global population will likely reach 9.0 billion by about 2050, mostly from developing countries. Urban populations will increase from today's 3.4 billion to well over 6 billion. With higher incomes and different tastes, diets in developing countries will shift from low- to high- value cereals, poultry, meats, fruits and vegetables. While this will constitute an improvement for many, this major shift in consumer preference for nutritional security is also likely to be accompanied by hunger and poverty in the countries with the poorest populations, while obesity rates as high as those now seen in wealthy countries would occur in others. Increased demand for fossil fuels for fertilizers and transport to meet growing food demands will likely change the prospects for biofuels

A report to be released at a pivotal global meeting on agriculture finds that transforming the agriculture agenda to meet the challenges of a warmer, environmentally-degraded world of 9 billion people will require changes "as radical as those that occurred during industrial andagricultural revolutions of the 19th and 20th centuries."

The comprehensive assessment, Transforming Agricultural Research for Development, suggests the need for massive reform of the architecture of what it terms a currently "fragmented global system of research and development," in order to better reach small-scalefarmers on the ground, while making food production more sustainable and the systems in which they are produced more resilient to future climatic and energy shocks.

The report, funded by a range of international organizations and development agencies, including the World Bank, European Commission, and the UK Department for International Development, provides a stage-setter at the first Global Conference on Agricultural Research for Development (GCARD), which has been tasked by the G8 to turn priorities on future needs in agriculture into constructive actions to reshape its future.

Nearly one thousand participants, including World Food Prize Laureates, heads of international organizations, agriculture ministers, farmers, civil society groups, community development organizations, leading scientists, and private sector innovators are expected to participate in the meeting, taking place 28-31 March in Montpellier, France.

The report, prepared by a team of experts led by Uma Lele and including Eugene Terry, Eduardo Trigo and Jules Pretty, builds on extensive consultations across all continents in 2009 and their considerable experience in global food and agriculture, and is undergoing review by stakeholders around the world. It will be formally presented at GCARD on Monday, 29 March.

According to World Bank estimates, some 1.4 billion people were already living in poverty in 2005, well before the 2007 food price increases and the 2008 financial crisis. Since the financial crisis, an additional 100 million people are now believed to have joined the ranks of the poor and hungry, according to both FAO and World Bank estimates.

"It is clear that the Millennium Development Goal of substantially reducing the world's hungry by 2015 will not be met. A major cause has been a steady decline in policy attention to agriculture and rural development," said Uma Lele, the lead author of the report and Former Senior Adviser at the World Bank.

"Little has been done by developed and developing countries alike to deal with the daunting challenge of hunger with long term- development assistance to agriculture and rural development. Rather as a flip side of development, short term emergency food and other emergency aid have increased."

Over the 1981 to 2007 period, the share of net aid flows to developing countries has become negative for Latin America and for East Asia, and it has declined substantially for South Asia. Even for sub-Saharan Africa, net aid has declined and less of it has been going to agriculture.

"Barring the three big countries of China, India, and Brazil, capacity of most developing countries in agricultural R and D has been winding down," said Lele. "We must make a quantum leap in building back up their capacity and translate government and donor pledges into concrete actions."

"There has been remarkable progress in food production over the past half-century, with historically unprecedented improvements when agricultural research and development were given primacy," said Jules Pretty, a global author and Professor of Environment and Society, Department of Biological Sciences, at the University of Essex, UK.

"But some of those benefits were spread unevenly, and there are big problems around the corner: climate change, the energy crunch, economic uncertainty, population growth, environmental degradation, and a shift in consumption patterns in emerging economies that are following the same unsustainable models found in the West. Substantial changes are needed in the levels and types of aid and the way it is given."

According to the report, the global population will likely reach 9.0 billion by about 2050, mostly from developing countries. Urban populations will increase from today's 3.4 billion to well over 6 billion. With higher incomes and different tastes, diets in developing countries will shift from low- to high- value cereals, poultry, meats, fruits and vegetables.

While this will constitute an improvement for many, this major shift in consumer preference for nutritional security is also likely to be accompanied by hunger and poverty in the countries with the poorest populations, while obesity rates as high as those now seen in wealthy countries would occur in others. Increased demand for fossil fuels for fertilizers and transport to meet growing food demands will likely change the prospects for biofuels.

"The business-as-usual model of how things have been organized over the previous 50 to 70 years is no longer an option. We have to go back to the drawing board," said Eduardo Trigo, a global author, Director of Grupo CEO, and Scientific Advisor to the International Relations Directorate of the Ministry of Science, Technology and Innovation of Argentina.

The authors contend that there should be enough knowledge and resources available-or that can be mobilized-to tackle the problems of poverty and hunger, if the system for doing so could be massively overhauled. The report sets an approach for transforming the current global system of cooperation in agricultural research for development into "a coherent whole so as to achieve more rapid, scaled-up and sustainable impacts on food security, poverty, and the environment."

The report and overall conference process are seeking to ensure that agricultural research for development will be more inclusive of both women and the needs of small farmers.

The report provides a holistic view of the myriad actors that currently form this fragmented global agricultural research system-the landscape of actors and funders in the agricultural system as it stands today; regional research organizations and their development needs; and a roadmap of guidelines for translating the products of agricultural research into larger and quicker development successes.

It includes references to some 300 pieces of research; a review of dozens of documents, international assessments and summits on the state of agriculture undertaken over at least two decades; and consultations with national governments, members of civil society, scientists, and other key players from all regions of the world. The consultations undertaken have involved direct inputs from over two thousand people.

Investments Needed

"We are in a paradoxical state where we are living in the age of knowledge, but the level of investments going to agricultural research is less than half of what it should be," said Trigo. "And there is ample evidence that these investments are tremendously profitable."

This pattern of concentration parallels what is happening in overall science spending throughout the world, according to the report. In developed countries, agricultural R and D has also become increasingly concentrated in a handful of countries, with just four countries (the United States, Japan, France, and Germany) accounting for 66% of all global public R and D conducted in 2000.

Similarly, just five developing countries (China, India, Brazil, Thailand and South Africa) undertook just over 53% of the developing countries' public agricultural R and D in 2000-up from 40% in 1981. Meanwhile, in 2000, a total of 80 countries with a combined population of approximately 625 million people conducted only 6.3% of total agricultural R and D.

To meet the backlog of underinvestment alone, the report calls increasing agricultural research investments in developing countries to 1.5 percent of agricultural GDP, more than double or triple the current investments in scientific capacity and institutions and delivery mechanisms at both the national and international levels.

Some analysts say that to meet FAO estimates of food demand in 2050, annual investments in developing countries of about US $210 billion gross or US $83 billion net in 2009 dollars would be needed annually after allowing for depreciation of the existing stock of capital. This is an increase of almost 50% over current levels. These needs would decline over time with increased efficiency in agriculture and decelerating demand for food, say the global authors.

Currently, the Consultative Group on International Agricultural Research (CGIAR), which was set up by the World Bank and wealthy country donors in the 1970s to develop new crop varieties, farm management techniques and innovations to farmers in the developing world, constitutes about 4-5% of the total global public sector expenditures on agricultural research, according to the report.

The CGIAR's Strategic Results Framework has estimated that public agricultural research and development for developing countries would need to increase from the current $5.1 billion to $16.4 billion by 2025 of which the $1.6 billion would need to be the CGIAR element. The report contends that this is the minimum amount needed since developing-country needs for research extend beyond the CGIAR's mandates.

"GCARD is intended to leverage the remaining 94-95%, which includes both public research systems of developed and developing countries which are often not responsive to the needs of smallholder farmers," said Lele. "With the 4-5% from the CGIAR, the objective is to get a much bigger bang for the buck on effectiveness and impact."

"Donors need to increase aid levels for capacity building and especially to the regions of the world with the greatest concentration of poverty; these include Asia with two thirds of the world's poverty and Sub-Saharan Africa with slightly less than a third. The $20 billion the G8 committed for food and agriculture over three years is too small. It also remains to be seen whether it will materialize," said Lele.

"In addition, CGIAR, which already has a track record in research would need to help make a case for additional investments in developing countries" said Eugene Terry, a global author and former Director General of one of the 15 CGIAR centers (Africa Rice/WARDA), Founding Director of the African Agriculture Technology Foundation, and Ex-Chair of the World Agroforestry Center (ICRAF).

The CGIAR is undergoing a reform process to ensure it has a greater collective impact, simplified governance, and clarified accountabilities with clear and distinct roles for both investors and implementers.

"It is clear that the issues of food insecurity and poverty, rather than the funding cycles of governments and donors, need to drive the strategic frameworks both of national agricultural research systems and of the CGIAR," write the authors.

Gaining Production Increases "Outside the Box"

"Without viable livelihoods, the resource-poor smallholder farmers will move to the cities in the future," said Trigo. "Addressing food security issues in urban areas is completely different than doing so in rural areas. The focus will have to shift to producing food by the poor for the poor. During the food crisis, we had food riots not in the rural areas, but in the cities."

Options deployed over the previous five decades for ensuring big productivity gains to meet the enormous and diverse food needs of the future are no longer on the table or the most sustainable options, say the authors. These include "extensification," or moving agriculture onto lands currently not being used. "We need to produce food for a growing population on the same piece of land," said Terry. "Sustainable intensification now has to be given high priority to reduce negative environmental impact."

To get the production increases needed, the authors call for a broader approach to agricultural research for development that departs from the traditional approach that keeps scientists who develop a technology separate from the process that delivers that new technology to farmers.

The report calls for greater participation amongst a broad range of stakeholders in the seed-to-table chain of events-from the rural farmer to the scientist, in addition to the players in between, including extension officers, the private sector, national and regional agricultural programs, and civil society.

It also calls for recognizing and drawing on the tremendous innovation of farmers themselves. According to the authors, agriculture is highly context-specific and needs to move away from the expectation that research advances can be applied as one recipe-or single models as silver bullets-developed globally and applied locally.

"Development problems cannot be solved by research alone, as research by itself can be a blunt instrument," said Terry. "Research has to be translated into real development outcomes. There are many pathways to achieve this, including through partnerships, but none of them involve linear solutions."

"Real partnerships with developing countries in leadership roles are needed to enable developing countries to address their problems in ways only they can," said Lele.

Closing the yield gap between the best yields and those realized by a large majority of farmers calls for increased investments in adaptive research, extension, and a variety of other delivery services which constrain growth, write the authors.

"If you can get the conditions right in agriculture, you've got millions of farmers, men and women, with ideas on how to improve things," said Pretty.

"If they could just have access to credit or fertilizer, they could go a long way. It is this locked-up innovation we have previously been unable to get at, because the poor are starving or hungry or powerless or excluded. We just have to find a key. The trouble is there are billions of keys. That's why you need the new architecture for agricultural research to keep finding the keys and unlocking the potential.”

Continuing Bee Collapse

A pretty good argument was laid out a year or so ago that a particular pesticide was the likely culprit.  By now that should have been clarified statistically.  Otherwise, what this continues to show is that we have no good ideas.

It is a good idea to rethink the role of pesticides.  We have developed a large arsenal and actually we keep developing new product.  It is way more appropriate to license pesticide usage on the basis of minimal residual effect.  I suspect that this is now possible.

It will certainly be resisted by the manufacturers who certainly do not want limitations on their marketing.  Yet the community wants it.  The general application of a specific agent across a biological region should also suppress refugia.  Such methods can be specifically tested on bees.

I do not believe that pest control was meant to include blanket suppression because this also suppresses the natural control agents.  Yet a wide variety of such agents must suppress any number of other species.

I think it is time to establish test ranges to learn more about what we are doing than continuing to rely on targeted testing as to simple efficiency.

After I wrote this short item on the subject of the plausibility of the pesticide theory, I was introduced to another important possibility.  It is the effect of microwave towers on bee populations.  The apparent cycle eliminates populations interacting with a given tower over about three years.  It also impacts wild bee populations.

I am inclined to listen simply because these insects rely on homing systems that surely take advantage of our old friend magnetite.  Microwaves will react and disturb such a system and it makes total sense for the insects to become lost or otherwise disoriented.

During the time period noted, microwave towers have gone up everywhere.  Bee keepers need to position hives as far away from those towers as possible.

Scientists stumped

by Staff Writers

Washington (AFP) March 29, 2010

http://www.seeddaily.com/reports/Scientists_stumped_as_bee_population_declines_further_999.html

The decline in the US bee population, first observed in 2006, is continuing, a phenomenon that still baffles researchers and beekeepers.

Data from the US Department of Agriculture show a 29 percent drop in beehives in 2009, following a 36 percent decline in 2008 and a 32 percent fall in 2007.

This affects not only honey production but around 15 billion dollars worth of crops that depend on bees for pollination.

Scientists call the phenomenon "colony collapse disorder" that has led to the disappearance of millions of adult bees and beehives and occurred elsewhere in the world including in Europe.

Researchers have looked at viruses, parasites, insecticides, malnutrition and other environmental factors but have been unable to pinpoint a specific cause for the population decline.

The rough winter in many parts of the United States will likely accentuate the problem, says Jeff Pettis, lead researcher at Department of Agriculture's Bee Research Laboratory in Beltsville, Maryland.

Winter figures will be published in April. But preliminary estimates already indicate losses of 30 to 50 percent, said David Mendes, president of the American Beekeeping Federation.

"There are a lot of beekeepers who are in trouble" he said.

"Under normal condition you have 10 percent winter losses.. this year there are 30, 40 to 50 percent losses."

He said the phenomenon probably results from a combination of factors but that the increased use of pesticides appears to be a major cause.

"I don't put my bees in Florida because the last couple of years there has been tremendous increase in pesticide use in the orange crop to fight a disease," he said.

"It's a bacterium and the only way to control this disease is to use pesticide... a few years ago they did not use any pesticide at all."

He said that pesticide use "has changed dramatically" and has made beekeeping "more challenging."

Research conducted in 23 US states and Canada and published in the Public Library of Science journal found 121 different pesticides in 887 samples of bees, wax, pollen and other elements of hives, lending credence to the notion of pesticides as a key problem.

Pettis said the finding of pesticide residue is "troubling."

"It might not be the only factor but it's a contributing factor," he said.

The best thing to help bees, he said its "to try to limit habitat destruction," leaving more natural areas in agriculture and in cities such so honey bees can have "a diverse natural environment."

Ironically, he said the problem stems from expansion of agriculture to feed the world. But in destroying bee populations, that can hurt crop production.

"The world population growth is in a sense the reason for pollinators' decline," he said.

"Because we need to produce more and more food to feed the world and we grow crops in larger fields. A growing world means growing more food and to do that we need pollinators. And the fact that the world is continuing to grow is the driving force behind the habitat destruction."

Sub Sea Volcano Near Italy

This is a worthy reminder that these monsters exist.  We are now able to inventory all such volcanoes.  Perhaps we should.  At least we can be aware that the possibility exists when we build sea side cities.  A global list would allow occasional monitoring although any activity itself will show up on the seismic record.

Here we have a very nice reminder of Santorin.  If this were to blow it would produce as big a mess.

There has to be a lot more in the ocean simply unnoticed.  Every atoll in the Pacific is one such.

Of course this volcano will not be doing anything soon.  It is just that it could.

Undersea volcano threatens southern Italy: report

by Staff Writers

Rome (AFP) March 29, 2010

http://www.terradaily.com/reports/Undersea_volcano_threatens_southern_Italy_report_999.html

Europe's largest undersea volcano could disintegrate and unleash a tsunami that would engulf southern Italy "at any time", a prominent vulcanologist warned in an interview published Monday.

The Marsili volcano, which is bursting with magma, has "fragile walls" that could collapse, Enzo Boschi told the leading daily Corriere della Sera.

"It could even happen tomorrow," said Boschi, president of the National Institute of Geophysics and Volcanology (INGV).

"Our latest research shows that the volcano is not structurally solid, its walls are fragile, the magma chamber is of sizeable dimensions," he said. "All that tells us that the volcano is active and could begin erupting at any time."

The event would result in "a strong tsunami that could strike the coasts of Campania, Calabria and Sicily," Boschi said.

The undersea Marsili, 3,000 meters (9,800 feet) tall and located some 150 kilometres (90 miles) southwest of Naples, has not erupted since the start of recorded history.

It is 70 kilometres long and 30 kilometres wide, and its crater is some 450 metres below the surface of the Tyrrhenian Sea.

"A rupture of the walls would let loose millions of cubic metres of material capable of generating a very powerful wave," Boschi said.

"While the indications that have been collected are precise, it is impossible to make predictions. The risk is real but hard to evaluate."

Atlantic Conveyor not Slowing

It forever amazes me when rather speculative theories find their way into textbooks and then return as fact with a new generation of scholars.  Oh well.  At this point no one wants to think that the really big event over ten thousand years ago was the crustal shift that I have been pushing which likely modified the conveyor belt pretty sharply.

Today we are able to note that the crucial part of the conveyor belt has sped up by twenty percent or so since 1990.  That means that the implied dynamics of the system has delivered twenty percent more heat to the Arctic than it has in the past.  We actually do not have such great data but we certainly seem to have the direction.

That heat was absorbed by the Arctic Sea.  It still is been absorbed by the Arctic Sea.  So unless one is an idiot, it is quite clear that a lot more heat got delivered directly to the Arctic by this mechanism and it provides a good explanation for the decadal deteriation of the sea ice presently been experienced.

In fact the heat was likely absorbed as a buoyant surface layer of warmer water that just happened to be larger than normal.  I cannot imagine a more effective way to reduce sea ice.

I think that we are looking at our principle agency for long cycle climate change and it is on a gentle rise.

NASA Study Finds Atlantic Conveyor Belt Not Slowing

by Staff Writers

Pasadena CA (SPX) Mar 26, 2010

http://www.spacemart.com/reports/NASA_Study_Finds_Atlantic_Conveyor_Belt_Not_Slowing_999.html

http://www.spacedaily.com/images-lg/global-ocean-circulation-lg.jpg

Illustration depicting the overturning circulation of the global ocean. Throughout the Atlantic Ocean, the circulation carries warm waters (red arrows) northward near the surface and cold deep waters (blue arrows) southward. Image credit: NASA/JPL

New NASA measurements of the Atlantic Meridional Overturning Circulation, part of the global ocean conveyor belt that helps regulate climate around the North Atlantic, show no significant slowing over the past 15 years. The data suggest the circulation may have even sped up slightly in the recent past.

The findings are the result of a new monitoring technique, developed by oceanographer Josh Willis of NASA's Jet Propulsion Laboratory in Pasadena, Calif., using measurements from ocean-observing satellites and profiling floats. The findings are reported in the March 25 issue of Geophysical Research Letters.

The Atlantic overturning circulation is a system of currents, including the Gulf Stream, that bring warm surface waters from the tropics northward into the North Atlantic.

There, in the seas surrounding Greenland, the water cools, sinks to great depths and changes direction. What was once warm surface water heading north turns into cold deep water going south. This overturning is one part of the vast conveyor belt of ocean currents that move heat around the globe.

Without the heat carried by this circulation system, the climate around the North Atlantic - in Europe, North America and North Africa - would likely be much colder.

Scientists hypothesize that rapid cooling 12,000 years ago at the end of the last ice age was triggered when freshwater from melting glaciers altered the ocean's salinity and slowed the overturning rate. That reduced the amount of heat carried northward as a result.

Until recently, the only direct measurements of the circulation's strength have been from ship-based surveys and a set of moorings anchored to the ocean floor in the mid-latitudes.

Willis' new technique is based on data from NASA satellite altimeters, which measure changes in the height of the sea surface, as well as data from Argo profiling floats.

The international Argo array, supported in part by the National Oceanic and Atmospheric Administration, includes approximately 3,000 robotic floats that measure temperature, salinity and velocity across the world's ocean.

With this new technique, Willis was able to calculate changes in the northward-flowing part of the circulation at about 41 degrees latitude, roughly between New York and northern Portugal. Combining satellite and float measurements, he found no change in the strength of the circulation overturning from 2002 to 2009.

Looking further back with satellite altimeter data alone before the float data were available, Willis found evidence that the circulation had sped up about 20 percent from 1993 to 2009. This is the longest direct record of variability in the Atlantic overturning to date and the only one at high latitudes.

The latest climate models predict the overturning circulation will slow down as greenhouse gases warm the planet and melting ice adds freshwater to the ocean. "Warm, freshwater is lighter and sinks less readily than cold, salty water," Willis explained.

For now, however, there are no signs of a slowdown in the circulation. "The changes we're seeing in overturning strength are probably part of a natural cycle," said Willis. "The slight increase in overturning since 1993 coincides with a decades-long natural pattern of Atlantic heating and cooling."

If or when the overturning circulation slows, the results are unlikely to be dramatic. "No one is predicting another ice age as a result of changes in the Atlantic overturning," said Willis.

"Even if the overturning was the Godzilla of climate 12,000 years ago, the climate was much colder then. Models of today's warmer conditions suggest that a slowdown would have a much smaller impact now.

"But the Atlantic overturning circulation is still an important player in today's climate," Willis added.

"Some have suggested cyclic changes in the overturning may be warming and cooling the whole North Atlantic over the course of several decades and affecting rainfall patterns across the United States and Africa, and even the number of hurricanes in the Atlantic."

With their ability to observe the Atlantic overturning at high latitudes, Willis said, satellite altimeters and the Argo array are an important complement to the mooring and ship-based measurements currently being used to monitor the overturning at lower latitudes. "Nobody imagined that this large-scale circulation could be captured by these global observing systems," said Willis.

"Their amazing precision allows us to detect subtle changes in the ocean that could have big impacts on climate."