Governments must realize that the greenhouse effect is damaging world heritage monuments such as the Parthenon, climatology experts said at the International Conference on Climate currently under way in Nairobi. Climate change is a grave threat to some of the greatest world heritage monuments, from Darwin’s favorite coral reef in Belize to the archaeological treasures of Scotland. Scientists have warned of the serious consequences of climate change, such as extreme weather conditions, mass population movements due to floods and droughts. But they have not managed to galvanize world governments into taking effective measures to curb activities that waste energy and cause pollution. In just a few decades, natural and man-made monuments may suffer partial or total destruction, say researchers from the Stockholm Environment Institute in their report titled «The Atlas of Climate Change: Mapping the Greatest Challenge to Humanity.» In many cases the effect of climate change will be immediate, with destruction caused by a rise in sea levels, floods and massive storms. For other monuments, mainly cathedrals and mosques, the threat comes from drastic changes in local climate. Even minor changes in humidity can have dramatic consequences, either by directly altering the structures themselves, or by affecting the chemistry and the stability of their foundations. It may seem a distant threat, yet such destruction has already begun, the researchers note. In 2002, for instance, floods that hit the Czech Republic caused serious damage to historic buildings such as theaters, museums and libraries, while an estimated 500,000 books and archived documents were destroyed. Apart from the Czech Republic, which the report lists among the states vulnerable to climate change, Thailand has already lost part of its cultural heritage to the effects of climate change, when floods swept away 14th century ruins in the cities of Sukothai and Ayutthaya in northeastern Thailand. Egypt is also at risk. Coastal erosion and flooding in the Nile Delta pose a risk to the monuments of Alexandria, such as the Acropolis of Qaitbey and some 12,000 archaeological sites, ranging from Viking-era ruins to medieval monuments. Many natural ecosystems that support local economies will not be able to withstand climate change. One of these is the coral reef of Belize, which Darwin referred to in 1842 as «the most marvelous reef in the West Indies.» The reef has already started to lose its color due to the rising temperature of the surface water, a process which is expected to intensify.