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With an uninterrupted 17-million year sediment record of Antarctic’s climatic past now available, scientists are hoping for unique new insights into the continent’s climatic past.

A few initial results of the Antarctic Geological Drilling programme (ANDRILL) were announced last week at the general assembly of the European Geosciences Union in Vienna. There is an online news story here.

Antarctica’s ice sheets, so it seems, respond more sensitively to climate fluctuations than has been assumed. During warmer periods, the West Antarctic Ice Sheet and its floating extension, the western Ross Ice Shelf, have shrunk substantially. Some 3.5 million years ago the ice seems to have disappeared completely for around 200,000 years. There were snow-capped mountains, alpine trees, gushing rivers, quiet lakes – the frozen continent was a place where you would love to go fishing or hiking, were it not for the midges.

The world was warmer then than it is today, but not substantially so. If temperatures continue to rise, glaciers in Antarctic’s warmer western part might begin to retreat again before long. A few million years ago, Antarctic melting probably raised sea levels globally by 10 metres or so. If history repeats itself, we’re headed for trouble.

Quirin Schiermeier

Posted by Quirin Schiermeier on April 24, 2008
Categories: Recent contributors, Categories, Conferences and Meetings, EGU 2008, Palaeoclimate, Quirin Schiermeier | Permalink | Comments (5) | TrackBacks (0)

If there was an eye in the sky keeping watch on our greenhouse gas emissions, what carbon crimes would it reveal?

The ability to measure greenhouse gases from space, soon to become a reality, could answer this question.

Currently, it’s virtually impossible to identify the exact source – and destination - of greenhouse gases, a prominent theme at this year’s European Geosciences Union conference in Vienna.

But, according to scientists speaking today at the conference, this is all set to change within the coming year when two major satellites designed to monitor greenhouse gases will be launched into space.

Due to leave Earth on December 15, the first of these is the Orbiting Carbon Observatory (OCO), a US$300 million-or-so innovation of scientists and engineers at NASA’s Jet Propulsion Laboratory in California. The Japanese version, known as the Greenhouse Gases Observing Satellite, or GOSAT, has an anticipated launch date in January or February 2009.

For a detailed low-down on the satellites and how they will work, see Amanda Haag’s news feature in Nature (subscription) last December. Since then, the scientists have mostly been testing and calibrating the instruments to make sure they work once they’re orbiting the Earth.

Within a year or two, if not sooner, they will enable scientists to identify major sources and sinks or carbon, says Charles Miller, one of the Principal Co-ordinators of the OCO mission. The greenhouse gas measurements taken by the instrument, which will orbit the planet 14.5 times per day, will be three times more precise than any trace gas measurements ever taken from space.

All-in-all, the missions represent an unprecedented effort to collect global climate data from space. While this is fascinating from a scientific perspective, it should also have some interesting political implications by enabling the easy identification of climate culprits.

“If one were to imagine a way to monitor or verify [emissions], then this would be the way to go”, says Miller. For instance, it should quash (or raise, depending on who you’re talking to) fears that nations claiming credits for avoiding deforestation under the Kyoto Protocol will be able to divert the problem elsewhere.

Miller says they often joke that the instrument could detect the greenhouse gas emissions of serious carbon heaveyweights from space. But while the new satellites won’t realistically help reporting on individual carbon crimes, it could act as a ‘big brother’ to keep countries in line with their Kyoto commitments. Personally, I’m curious to know the OCO’s own carbon footprint!

That’s all from me from this year’s European Geosciences Union conference in Vienna. Over and out….

Olive Heffernan

Posted by Olive Heffernan on April 18, 2008
Categories: Atmospheric Science, Conferences and Meetings, EGU 2008, Olive Heffernan, Technology | Permalink | Comments (0) | TrackBacks (0)

The North Atlantic Ocean may still be an active storehouse for atmospheric carbon dioxide, said scientists at the European Geosciences Union here in Vienna yesterday.

Following evidence published last year showing that both the Southern Ocean and North Atlantic Ocean have weakened as carbon sinks in the past two decades, the new results suggest that the trend has recently reversed in the North Atlantic.

Scientists have feared that the weakening trend could be a long-term impact of global warming and that it could be typical of the ocean as a whole, which absorbs an estimated 25 per cent of anthropogenic carbon dioxide emissions yearly. If the ocean switches from a storehouse to a source of the greenhouse gas, this would jeopardise efforts to stabilise atmospheric greenhouse gas levels.

Speaking at a press conference at the EGU assembly yesterday, Ute Schuster from the University of East Anglia in Norwich, UK and Christoph Heinze at the University of Bergen, Norway, presented the results of a yearly analysis of carbon dioxide fluxes across the North Atlantic Ocean.

Previously, Schuster and colleagues showed that carbon uptake by the North Atlantic had halved between the mid-1990s and the early 21st century. But further analysis of the data on a year-by-year basis has shown that the uptake of carbon dioxide in the region has been increasing since 2002 and showed an even greater increase, relative to the early 2000s, in 2005.

The researchers caution that the results are preliminary and are not yet published. The coverage was poor in 2006 and they have not yet finished the analyses for 2007, but they say that the results so far indicate that the trend in weakening of the North Atlantic carbon sink is not linear.

The reasons for this variation are unclear. “I personally think we can’t say with confidence that the trend [in weakening sinks] is attributable to [anthropogenic] climate change”, says Schuster. Surface circulation in the North Atlantic has changed in recent years, she says, but these changes could be due to natural climate variability. Specifically, the North Atlantic Oscillation, a large-scale atmospheric pattern that has important impacts on European climate, could be influencing the rate of carbon dioxide uptake.

Continue reading "EGU: North Atlantic Ocean may regain status as carbon sink" »

Posted by Olive Heffernan on April 17, 2008
Categories: Biosphere feedbacks, Climate Science, Conferences and Meetings, EGU 2008, Ocean science, Olive Heffernan | Permalink | Comments (0) | TrackBacks (0)

Yesterday evening , we held a 'Meet the Editors' event at the Nature stand here at the European Geosciences Union conference, and invited scientists to join editors from Nature Geoscience and Nature Reports Climate Change for beer and pretzels.

Either the word on the street that geoscientists have a great fondness for beer is not simply an urban legend, or the research community is very interested in how we're extending our reach further into the earth sciences. I suspect it's a combination of both.

Most of those I spoke with asked one or more of the following:

Should I submit my paper to Nature or Nature Geoscience?

What are the chances of getting my manuscript published in Nature Geoscience?

If my paper is rejected from Nature, can I resubmit to Nature Geoscience?

When will Nature Geoscience have an impact factor?

Why did you cover such and such a story in Nature or on Nature Reports Climate Change? (geoengineering was a big one here; I guess readers were curious about why we might cover something that's still quite conceptual, such as the Lovelock and Rapley proposal). Personally, I think such topics are worthy of discussion within the scientific community especially at the conceptual stage. I for one, am interested in whether our readers think that research efforts and funding should be directed towards such big potential solutions with high risk of failure).

Others were curious as to why Nature, recognised for its rigorous editorial control, has so firmly embraced blogging, which again raises the split opinions on whether web 2.0 is a worthwhile means of communicating science, as discussed recently here and on RealClimate.

Continue reading "EGU: Meeting the scientists " »

Posted by Olive Heffernan on April 16, 2008
Categories: EGU 2008, Olive Heffernan | Permalink | Comments (1) | TrackBacks (0)