In 2050, the earth could be ravaged by hurricanes and droughts, and populated by millions of climate refugees. It would be the result of the world's failure to act on time, despite seeing the writing on the wall.
A bleak glimpse into the future
In 2050, young people with average incomes in Germany will grow up listening to their grandparents' tales of holidays in Venice. They themselves are unlikely ever to go on a more adventurous vacation than a cycle tour along the River Elbe - so long as it hasn't burst its banks.
With a barrel of oil costing over $600 (453 euros), anything else has become prohibitively expensive. Private cars and non-essential flights are a luxury that few can now afford. Welcome to the future.
The international community's efforts to reach binding agreement on tackling climate change have all failed. When the Kyoto Protocol ran out in 2010, it was never replaced.
The demands of the emerging nations were too great, as was the industrialized nations' refusal to compromise. The world's main climate offenders were unwilling to foot the bill for repairing the damage to the planet, nor would they commit to any long-term reduction of carbon emissions.
Drastic spike in global warming
Many regions will suffer from acute water shortages
The results are palpable. In 2009, the CO2 global average concentration in the Earth's atmosphere was about 0.0387 percent by volume, or 387 parts per million by volume (ppmv). By 2050, it has reached 675 ppmv.
Global warming has gathered pace even faster than was predicted in the early 21st century. The average temperature is now four degrees higher than it during the beginning of the industrialization, and researchers expect a further rise of 4 to 5 degrees by the end of the century.
But levels of global warming vary dramatically from region to region: parts of Europe have actually witnessed a drop in average temperatures due to the weakening of the Gulf Stream. In stark contrast, the Arctic and the North Pole have experienced a record rise in temperatures of almost 8 degrees.
But increased carbon levels in the atmosphere are not the only reason for the galloping pace of global warming. While it has triggered some processes which speeded up further warming, other effects have mitigated it. With the balance between these positive and negative feedbacks serving as a major cause of uncertainty in climate predictions, scientists were unable to forecast these ‘feedback effects.'
The thawing of permafrost in northern Russia and Canada, for example, accelerated global warming because methane was released in the process - a relatively potent greenhouse gas with 20 times the global warming potential of carbon dioxide.
Cities will be hard hit by natural disasters such as floods
The greenhouse effect has not only transformed Siberia and northern Canada into wastelands; it has also led to disastrous weather extremes.
By 2050, the frequency of typhoons and storm floods has increased in tropical countries. The islands of the Philippines are beset by strong coastal storms. Heavy rainfall regularly leads to landslides, which have already claimed entire villages.
Moreover, despite the heavy rainfall, the country is suffering from an acute shortage of freshwater: seawater had filtered into the country's subterranean freshwater reserves and made it undrinkable. Another consequence is that it has increased salinity levels in soil.
200 million climate refugees
The repercussions are severe. Viable farmland is urgently required to meet the needs of the world's population, which has now reached 9 billion (compared to 6,7 billion in 2009). 200 million of them are climate refugees.
Droughts will drastically raise the number of climate refugees in the world
A percentage of them come from small atolls in the Pacific Ocean and the densely populated delta regions along the rivers Ganges, Mekong, Nile and Brahmaputra, which flooded as a result of rising sea levels.
But the majority comes from central Asia and Africa. These people are not fleeing flooded regions, but the droughts that have led to mass starvation in many parts of the world. In Africa alone, almost one quarter of the continent's 1.8 billion inhabitants are affected by water shortages.
Mass migration present countries with new sets of problems: India in particular has been overwhelmed by waves of refugees from neighboring Bangladesh. India's population now numbers 1.9 billion and its government is unable to provide sufficient food and medication for the refugees living in camps on the Indian border.
Despite United Nations support, the spread of diseases such as cholera cannot be stemmed, and are soon proliferating even outside the refugee camps.
But the effects of climate change are not all negative. By and large, northern Europe has been spared extreme weather, and Scandinavian countries are enjoying milder climates than they used to. Northern Scandinavia in particular is home to large areas of land that can be used for agriculture.
The collapse of ecosystems
But many ecosystems have collapsed. Vulnerable coral reefs and mangrove woods have been destroyed by rising sea temperatures and levels, and a large part of the Amazon rainforest has been reduced to a steppe. Many plant and animal species have died out.
In 2050, mankind has paid a high price for its own survival - more than it would have cost to curb climate change in the first decades of the 21st century.
Today, in 2010, experts agree that well-off states only need to give up a small fraction of their wealth to prevent the worst.
Michaela Fuehrer (jp)
Editor: Sonia Phalnikar
This article is based on data and forecasts complied by the German Development Service, the UN, the International Organization for Migration, the Intergovernmental Panel on Climate Change (IPCC) and the Potsdam Institute for Climate Impact Research.