<![CDATA[A group of scientists from Columbia University have revealed the results of the newest drought atlas for the Old World, covering 2,000 years of climate data gathered from samples taken from tree rings. The drought history of the European continent has long been recorded only in historical documents, often concerned with local regions and thus inappropriate for a larger-scale study of droughts in Europe and the Mediterranean. However, the Old World Drought Atlas, spearheaded by Columbia University’s Tree Ring Lab co-founder Edward Cook, has provided a scientific method to analyze and interpret actual data gathered in the field to provide a missing piece of the puzzle. This isn’t Cook’s first attempt at constructing drought atlases based on tree ring data. The scientist and his team have also conducted evidence gathering and aggregating for Asia and North America in two previous studies, thus completing an overall study of the Northern Hemisphere’s climate over the last two millennia. In a press release published by Columbia University, Cook says that this newest atlas will be able to fill a significant geographic gap when it comes to modeling climate variation patterns over time. The data is crucial for scientists attempting to test climate change and climate forcing hypotheses, the scientist added, remarking that the newly-completed data sets will also prove highly useful in understanding what causes highly destructive so-called “megadroughts.” Historical records have their place, Cook stated, even going so far as to call them “wonderful” for small-scale pattern recognition. The problem is that limiting data to just a single spot on the map isn’t going to provide clues as to what caused weather pattern or climate oscillation. However, a drought atlas can show such broader-scale patterns and could shed some light on the nature of certain climate phenomena such as the Atlantic Multi-decadal Oscillation. This variation in the temperature of the North Atlantic’s surface hasn’t been subjected to enough study to determine if the oscillation is a natural occurrence or if it’s a result of anthropogenic involvement in the climate system. Cook hopes that climate modelers and climatologists will be able to use the new data from the Old World Drought Atlas in conjunction with the North American and Asian atlases to get to the bottom of the issue as well as other climate variations the Northern Hemisphere may be experiencing. Drought and flood conditions can of course have serious impact on human civilizations in the form of lost harvests, leading to instances of famine or the spread of plague that can disrupt human habitation and shift the balance of power in a region. This is as true historically as it is in the modern day; through learning if there are repeated patterns, it can help people plan for the future. For more information: www.advances.sciencemag.org]]>