The world's top scientists won’t have to travel far to witness the impacts of climate change, as the Interational Panel on Climate Change meets to finalise a landmark report on global warming in the Spanish port city of Valencia.
Valencia is in fact the heart of a coastal belt which is cowering at the prospect of desertification.
“Many people think desertification affects only Africa, Asia or Latin America,” Juan Sanchez, a department head at the Centre for Research on Desertification (CIDE) near Valencia. “But we are also at risk.”
Most of Spain suffers dry spells but in key regions aridity has become chronic, driven by human development and changing rainfall patterns – and worse is likely to come.
Around one-seventh of Spain is at high risk of desertification, according to CIDE's estimates.
Those areas most at risk are the Canary Islands, where 57 percent of the territory is threatened, and two eastern provinces on the Spanish mainland, Valencia (29 percent) and Murcia (37 percent).
The United Nations estimates that six percent of the territory of Spain, the most arid country in Europe, has already been irreversibly damaged.
The environmental group Greenpeace believes Spain's climate has begun to “Africanise”.
Spain is not alone in this problem, for much of the northern Mediterranean rim faces worsening water stress.
In February, the European Environment Agency (EEA) predicted that by century's end, temperatures in Europe would rise by between 2.0 degrees Celsius and 6.2 C, with eastern and southern Europe facing increases at the higher end of the range.
It singled out southern Spain, along with southern Italy, Greece and Turkey as regions where the “recharge season” of replenishing aquifers with fresh rainfall would shorten dramatically, reducing water for farms, cities and hydropower plants.
The problem is being worsened by water-thirsty businesses such as tourism, golf courses and farm irrigation, by pollution and by roads and buildings which drain water away rather than let the precious substance soak into the soil.
“The Mediterranean is especially vulnerable and faces the threat of large-scale migration and the disruption of local economies,” said Antonio Navarra, of Italy's National Institute of Geophysics and Vulcanology.
“We are looking at major impacts that could put tremendous stress on agriculture, water management, energy production and tourism.”
In April, the IPCC warned that availability of fresh water in badly-hit Mediterranean countries could fall by as much as a third by 2100.
In Sanchez's research centre, in mountains 20 kilometres from Valencia, a dozen scientists have been studying desertification since 1996 to try and halt the advance.
A big focus of their research is local soil erosion.
The region suffers devastating fires in the summer and is then drenched for several days every autumn by torrential rains. Another problem is rising salt levels, caused by irrigation.
“If we continue to destroy forests through fire and the salinisation continues, a large part of the soil in the region could be damaged within 40 years,” said Mr Sanchez.
Climate change is “linked to desertification in a lot of ways,” he said.
“In 25 to 50 years, if we do not stop the process of climate change, temperatures will rise, torrential rains will be more intense and erosion will increase.”
IPCC under scrutiny
The IPCC's five-day conference is to seal a “synthesis report” of a massive three-volume assessment, issued this year, that spelled out current knowledge about global warming, its likely impact and the estimated costs of dealing with it.
But beneath its newly-won fame, the Intergovernmental Panel on Climate Change (IPCC) is under intensifying scrutiny about some of its key processes.
Some voices, including from within the IPCC itself, fear the panel's grand report will be badly out of date before it is even printed.
Others quietly criticise the organisation as being too conservative in its appreciation of the climate threat.
The document to be issued in Valencia next Friday boils down a 2,500-page, three-volume assessment issued earlier this year, the first IPCC review of climate change since 2001.
The upcoming “synthesis report,” comprising a summary for policymakers of 25 pages, and a technical document of around 70 pages, puts in a nutshell the evidence for climate change, its likely impacts and the options for tackling it.
The analysis carries huge political weight. It will be a compass for guiding action on climate change for years to come, starting with a crucial UN conference in Bali next month.
Report ‘already out of date’
But some experts are worried, fearing that the IPCC's ponderous machinery, which gives birth to a new review only every five or six years, is falling dangerously behind with what's happening to Earth's climate systems.
The new report notably fails to take into account a batch of dramatic recent evidence, including the shrinkage of the Arctic ice cap, glacier loss in Greenland, a surge in levels of atmospheric carbon dioxide (CO2) and an apparent slowing of Earth's ability to absorb greenhouse gases, they say.
Taken together, say the sources, these phenomena suggest climate change is be occurring faster than expected — and may even unleash “tipping points” that could uncontrollably accelerate the damage.
“Over the past several years we have realized … that the speed at which changes can occur — such as ice sheet disintegration and resulting sea level rise — is much faster than IPCC has estimated,” leading climatologist James Hansen, who heads the NASA Goddard Institute for Space Studies in New York, said.
“We are now in a situation where the luxury of super-caution and reticence poses a danger for the planet and all its creatures,” he said.
French scientist Jean Jouzel, who has been deeply involved in the IPCC report, acknowledges that its estimates about rising sea levels — which could affect hundreds of millions of people — are half of what more recent studies indicate.
Another weakness of the IPCC, say others, is a tendency to shy away from controversy.
The more forceful the panel's conclusions, the more pressure it will put on policymakers to adopt measures — some of them politically costly – ranging from carbon taxes and mandatory caps on CO2 emissions to massive investment in renewable energy.
Too often, draft text that highlights the possible consequences of warming gets watered down in the final version, say these critics.
British scientist James Lovelock blames the consensus rule that governs IPCC proceedings, enabling government representatives to meddle with “forthright and inconvenient forecasts” made by experts.
“The IPCC has a history and a habit of ignoring many of the big issues that hint at policy or policy analysis,” agreed Tom Downing, director of the Oxford Office of the Stockholm Environment Institute and a lead author of the report.
He pointed to the draft report to be hammered out in Valencia, saying it had “barely a page” on vulnerability to climate change and how to cope with it.
Action ‘the real issue’
The IPCC, jointly launched 20 years ago by the UN Environmental Programme (UNEP) and the World Meteorological Organisation (WMO), shared this year's Nobel Peace Prize with former US vice president Al Gore.
Pep Canadell, executive director of the Global Carbon Project based in Australia, says the panel's caution and rigour had helped create awareness that climate change was a genuine and pressing issue.
But it was time for the IPCC to move to a faster and more assertive track, Mr Canadell suggested.
“We are no longer in the business of convincing governments that the problem is real,” he said. “The issue now is what to do and how fast it needs to be done.”