Changes in the annual life cycles of plants and animals are a good footprint of climate change in middle latitudes. But it is a footprint that is less easy to detecet than melting sea ice or glacier retreat.

Eye-observations by millions of gardeners and nature lovers suggest that plants green and flower earlier in spring, and that leaves begin to colour and fall off later in autumn, than they did just a few decades ago. So where will we end then? Will pollen soon be in the air all year round - a nightmare for allergic persons?

Scientists such as Annette Wenzel, an eco-climatologist at the Technical University of Munich, use remote sensing technologies, models, and in-situ observations to study the response of plants to warming temperatures. But the corelation between warming and ‘phenology’ is less clear than one might expect.

One reason, says Wenzel, is that the European phenology network of around 8,000 observation sites is a rather unevenly distributed affair. The vast majority of sites are located in Germany and its neighboring countries, whereas the whole of Scandinavia has just a handful of sites, and Italy not a single one. To make matters worse, the species composition differs from site to site, making it difficult for scientists to define a Euroean-wide ‘green-up’ index.

Even extreme climatic events don’t provide a clear picture. Warm spells have become significantly more frequent in Europe during all seasons, and cold spells less fequent, from 1990 onward than prior to 1990. Wenzel has looked at how recent warm and cold spells affected the flowering of cherry and apple trees, and the sowing and harvest time of winter wheat. Fruit trees and wheat farmers do respond to climate anomalies, she found. But, again, the correlations where not excitingly strong.

Weather-related crop failures are not included at all in the European phenology database. Scientists trying to establish connections between crop failures and climate change rely mostly on anecdotal evidence and media reports.

Quirin Schiermeier

Posted by Quirin Schiermeier at 03:47 PM | Permalink

It’s a warm and sunny spring day today in Vienna can you guess then whether the coming summer will be colder or warmer than usual? Well, if you think that you hardly have more – though certainly not less - than a 50% chance of getting it right you’re, uhm, right. But guess what: Supercomputer-powered seasonal climate forecasts don’t do much better.

Seasonal climate predictions work relatively well only in the tropics. In Europe and North America their predictive skills are still pretty poorer, meaning that forecast and observed climatology are often two very different things. And in some regions seasonal forecasts are actually worse than plain guessing.

This means that seasonal climate forecasts don’t yet provide reliable, if any, guidance for farmers, tourism managers, forest fire fighters, or for me and you. The idea that slowly varying boundary conditions, such as sea surface temperature distribution, snow cover and soil moisture, push the climate in a certain direction is well-established. But statistical climatology is one thing, daily wheather is another.

Andreas Weigel of the Swiss Weather Service, a rising star in the seasonal forecast community, made a few suggestions here at the EGU as to how predictive skills could be improved. Using more than one climate model is one promising possibility, statistical post-processing an re-calibrating forecasts is another, he explained in his well-received medal award lecture today

In the same session, Marie Boisserie of Florida Stae University in Tallahassee reported that when she included realistic initial soil moisture conditions to a climate model it greatly improved its predictive skills. Two-month forecasts of summer temperatures and precipitation in the US were more than twice as accurate than without the precipitation-derived soil moisture data.

Problem is that as yet there exists no reliable global observational database of soil moisture.
All eyes are now on the European Space Agency’s Soil Moisture and Ocean Salinity (SMOS) mission, designed to observe soil moisture over the Earth's landmasses and salinity over the oceans, to be launched in June.

Quirin Schiermeier

Posted by Quirin Schiermeier at 11:36 AM | Permalink

A record number of 9,000 or so scientist has come to the always charming Austrian capital of Vienna for this year’s general assembly of the European Geosciences Union, the biggest such meeting this side of the Atlantic.

In search of some local colour I went this morning to a session on climate and mountain hydrology. Vienna, just like Munich, Milan, Grenoble and many other cities in vicinity to the Alps, depends on drinking water from mountain streams and reservoirs. The Alps are in fact a water tower for all the surrounding lowlands; and although there is no real water shortage, Alpine regions are highly sensitive to climate change.

Bruno Schädler of the University of Bern in Switzerland explained that a two degree increase in average temperature is equivalent to a 360 metres decrease in altitude. Total glacier area in the Alps is likely to decrease by more than 50% under this pretty realistic scenario. Projections are that more winter precipitation will fall in the form of rain, and less as snow, and that increased evapotransporation will reduce the amount of summer rainfall. All this will change the runoff regimes of Alpine rivers and streams, and hence the availability of water competing purposes including irrigation, hydropower, and tourism. But how, where and when these changes will come, and if they will bring more floods, or more low water, or both, is still extermely difficult to say. Regional climate models, for example, don’t represent complex Alpine topography, hydrology and meteorology, which differ from one valley or catchment area to the next.

Perhaps that explains why there is little, if any, adaptation to climate change happening in the Alps. Indeed, adaptation measures are driven by concrete events and economic requirements – such as lack of snow in a skiing ressort – rather than by climate change predictions. This is the result of ongoing regional case studies in six Alpine regions of Austria, Slovenia, Italy, France and Switzerland. Planning and management tools which consider climate change are almost totally absent, found Andrea Prutsch of Austria’s federal environmental agency, who coordinats the studies. Water-consuming artificial snow making is just one example of frequently happening cases of ‘maladaptation’. By and large, she said, adaptation to climate change in the Alps suffers from a widespread lack of data, monitoring and knowledge.

The science of climate change has come a long way. But this little Alpine saga shows that it has not yet arrived in the centre of society.

Quirin Schiermeier

Posted by Quirin Schiermeier at 12:49 PM | Permalink

Economists? Are cold-hearted, says the dictionary of accepted ideas. Now, Richard Tol, an environmental and energy economist at the Economic and Social Research Institute in Dublin is also a bit of an enfant terrible in his guild. So I, for one, was not surprised that his whistle stop at the EGU sent some palpable shockwaves through the large and well-filled lecture hall D here.

Tol talked about the economic impact of ocean acidification on the tourism industry. People ‘purchase’ the service of coral reefs (which are beginning to severely suffer from rising ocean acidity - a result of increased CO2 uptake by the seas) by going scuba diving in, say, the Caribbean, he explained. Coral reef tourism is however only a small part of the global tourism industry. The economic damage caused by less people coming to places like Belize or Martinique, although painful for these island communities, will amount to no more than 10 to 70 million dollars per year, he argued. A mere trifle.

But his reasoning drove some people mad. After the session Tol was heavily attacked by angry listeners for his (allegedly) deliberately playing down the environmental problems associated with ocean acidification. He had a hard time trying to explain that he didn’t mean to say that other impacts, such as on biodiversity, fisheries or coastal protection, did not matter from an economic standpoint. The sole reason why he focused exclusively on recreation was that impacts on tourism are the only ones that economists can currently hope to determine with reasonable reliability. But his point didn’t really get through.

The current rate of ocean acidification is something the world hasn’t seen in 20 million years, said one biologist. Neither has it ever seen democracy arriving in China, Tol replied.

So, are economists – or is Tol – outfitted with a cynical, die-hard materialist view of the world? No, they aren’t. What this little argy-bargy really goes to show is that the (much-needed) inclusion of economists to the climate debate is sometimes hampered by fear of contact between the two academic communities. That’s bad. So mind, rumours of economists lacking heart and soul are greatly exaggerated.

Posted by Quirin Schiermeier at 06:38 PM | Permalink

Global sea levels could rise by up to 1.5 metres by the end of the century, Svetlana Jevrejeva of the Proudman Oceanographic Laboratory in Liverpool told the EGU this morning.

Jevrejeva and her team reconstructed seal levels for the past 2,000 years, and then used a non- linear equation relating sea levels to temperature change to predict future sea level rise. Unlike the Intergovernmental Panel for Climate Change (IPCC), whose most recent prediction of sea level rise is three times smaller, the team incorporated into their prediction the rapid response to global warming of large ice sheet’s, such as Greenland’s.

Interestingly, Jevrejeva arrives at an even higher range (0.8 to 1.5 metres) than had Stefan Rahmstorf, an oceanographer at the Potsdam Institute of Climate Impact Research, just prior to the release of the 2007 IPCC report . Using a similar semi-empirical approach, but assuming a linear relationship between temperature and sea level change, Rahmstorf projected sea level rise in 2100 of 0.5 to 1.4 meters above the 1990 level. In a technical comment published in Science, Jevrejeva and others criticized his approach for “not meaningfully” contributing to quantifying uncertainties in the prediction of future sea-level rise.

The global sea level currently rises by 3.5 millimetres per year, as the combined result of thermal expansion of ocean water, glacier melting, and changes in the global hydrological cycle. Sea level rise by 1.5 meters would result in the loss of most of Bangladesh, and threaten low-lying regions around the world. In China alone, some 100 million people would need to be displaced if sea level were to rise by one meter or more.

Posted by Quirin Schiermeier at 10:07 AM | Permalink

It’s this time of year again – the European Geosciences Union’s (EGU) General Assembly is on.

Some 8,000 earth scientists have made it this year to the charming Austrian capital of Vienna. All sessions I went to today were well-attended. The discussions, in the lecture rooms and on the floors, were lively as ever.

The sessions this morning about mountain hydology, glaciology and the cryosphere – ice and snow, that is – were quite a treat. I listened to a pretty provocative exchange of views on arctic sea ice retreat. Are estimations about the rate of the retreat still to conservative, or is the demise of ice exagerrated? Some scientists believe that arctic ice is merely in a high flow state, and that the massive export through narrow passages of arctic ice into warmer waters will be more or less back to normal at some point. Optimistic!

The retreat of mountain glaciers, which provide a reliable water resource for many lowland regions, is one of the most striking signs of global warming. But glaciologist warned today that the behaviour of many large glaciers is worryingly understudied. Well, not in the European Alps or the Rocky Mountains. But Indian or Chinese earth scientists are often not the outdoor fanatics which most of their European or North American colleagues doubtlessly are (the uninformed passer-by could easily mistake the EGU for an assembly of mountaineers

Continue reading "Brave mountaineers" »

Posted by Quirin Schiermeier at 07:40 PM | Permalink

The EGU goes on until Friday, but my time here is over. It has so far been another solid European geosciences meeting, although certainly not all talks were as good as you might hope.

One thing is language. The organizers ask that all lecturers must be able to give their talks in ‘more or less’ fluent English. Well, I certainly attended a few talks which suffered more than just a little from, err, let’s say ‘handicapped’ English.

Questions from the audience were encouraged, and usually they do add interesting aspects to a given topic. But discussion doesn’t make much sense if a lecturer seems not to understand what he or she is being asked. There is an issue of politeness and consideration: Do you really need to query someone in a strong Australian accent if it’s plain to see that the poor guy up there – Malaysian, Ukrainian, French, whatever - is in deep linguistic trouble?

Another thing is the use of formula in presentations. Of course, mathematics is part of the game, whether in remote sensing or in modelling fluid dynamics. But if your slides contain little else than rows and rows of equations you can’t hope to reach out to anyone except to the die-hard experts.

But these are minor points. By and large the meeting had, and has still, plenty of enlightening talks to offer. Indeed, some North American attendees told me they prefer the more human proportions of the EGU to its oversized American counterpart, the annual AGU meeting. Vienna’s ‘old-Europe’ charm, I would say, adds quite a lot to the appeal of the EGU.

And, after all, the meetings serve not least as a marketplace for new ideas, jobs and collaborations in the geosciences. I don’t know how many participants have teamed up with new scientific partners, and it’s hard to guess how many fruitful ideas have been conceived during these days. But from the many happy faces I saw during sessions I guess it must be plenty.

Posted by Quirin Schiermeier at 01:50 PM | Permalink | Comments (1) | TrackBacks (0)

Some pop artists, including Madonna, have been accused of hypocrisy because their life styles are not exactly compatible with the climate-awareness they are going to raise at the Live Earth concert at Wembley Stadium in London on July 7. Can the same be said about scientists who fly around the world to attend the EGU?

A session yesterday evening about whether the meeting’s ‘carbon footprint’ is justified was not overwhelmingly well attended. In the end, 100 or so people showed up. Well, it was a perfectly fine spring day in Vienna, so no wonder that the meeting had partly shifted outdoors. Hundreds of scientists were busy ‘networking’ in the sunshine all day. Today it’s raining.

Some 8,000 scientists from almost 100 countries are said to be here. Someone has calculated that together they have travelled 15 million kilometres – this is 400 times around the world – to come to Vienna. The planes, trains and cars (only one participant is said to have taken the bicycle) which brought them here have emitted 5,000 tonnes of CO2, roughly the annual emissions of 2,500 EU citizens. Too much?

Yes, say some. Why go to a meeting at the other side of the world when you don’t really interact much with other parts of your university. Ok, you’ll hear a few talks and do a little networking. But then, aren’t we all swamped with information every day anyways?
Video conferences and email interactions could do the whole networking thing just as efficiently as physically going to meetings, argue the very physically present critics.

That’s well-meant. But do we really want to create a world of scientific homies?
No, says John Ludden, the president of the EGU. We should rather increase the carbon footprint, and the outreach, of the EGU, he counters. To really start tackling the problem of climate change we must bring more, and other, people - energy experts, economists, power plant engineers, scientists from India and China – to the EGU. The benefits easily outweigh the meeting’s carbon footprint. After all, he says, the coming together of earth scientists spins off ideas how to mitigate environmental issues and perhaps save the planet.

And why not plant a few trees or invest in carbon ‘offsetting’ projects?
“Rather than giving money to some Mickey Mouse offset company we should invite more people,” says Ludden.

Posted by Quirin Schiermeier at 09:11 AM | Permalink | Comments (1) | TrackBacks (0)

Researchers pin down when we'll know the effects of climate on water flow.

Is the powerful Atlantic current that has a major role in ocean circulation slowing down? We won't know until we have collected more than 20 years' worth of continuous measurements, researchers said on Monday at the general assembly of the European Geoscience Union in Vienna, Austria.

Read the story here.

Posted by Nicola Jones at 06:03 PM | Permalink

I am a bit at loss now, standing here between the tall concrete buldings that surround the Vienna Conference Center in the Kaisermühlen district of the Austrian capital. Kaisermühlen-Blues, it occurrs to me, was the name of a succesful 1990s TV series that ran on Austrian television.

It is the opening day of the EGU’s general assembly, the grand parade of European Geosciences. The problem is I can’t get in. The guys at the registration desk can’t find the badge with my name on it. Well, that can happen. Do I have a press ID? Uhm, no. Would my Nature business card be ok perhaps? No, it would not.

I’m told I have to apply to the press office somewhere inside the conference centre. That’s fair enough I guess, so I walk over. It’s only when I realize that without the damn badge the security blokes won’t let me pass that the Kaisermühlen-Blues comes to mind. It’s a dilemma, sort of.

Now, I am a reporter. So I hang around the main entrance, inconspicuously waiting for a moment when both guards will be distracted by some other trouble-makers. Sure enough, after a short while I manage to sneak in unnoticed. Fifteen minutes later I have got my badge and everything else I need to do my job here.

Continue reading "EGU: The great parade" »

Posted by Nicola Jones at 07:19 AM | Permalink | Comments (1) | TrackBacks (0)

Is snow disappearing from European mountains? What happens if you drill into an earthquake zone? And what, exactly, is the carbon footprint of a meeting of scientists gathered to discuss these questions?

Join Quirin Schiermeier on our newsblog for diary reports from the European Geosciences Union annual gathering in Vienna. He'll be sending back news from 16-18 April.

While you're at it, why not also check out our climate change in focus?

Posted by Nicola Jones at 01:49 PM | Permalink