Ecological and societal disruptions by modern climate change are critically determined by the time frame over which climates shift. Camilo Mora and colleagues in the College of Social Sciences' Department of Geography at the University of Hawaii, Manoa have developed one such time frame.
The study provides an index of the year when the mean climate of any given location on Earth will shift continuously outside the most extreme records experienced in the past 150 years.
Areas in the tropics are projected to experience unprecedented climates first - within the next decade.
Under an alternate scenario with greenhouse gas emissions stabilization, the global mean climate departure will be 2069.
The scientists calculated the index for additional variables including evaporation, precipitation, and ocean surface temperature and pH. When looking at sea surface pH, the index indicates that we surpassed the limits of historical extremes in 2008.
The index used the minimum and maximum temperatures from 1860-2005 to define the bounds of historical climate variability at any given location. The scientists then took projections for the next 100 years to identify the year in which the future temperature at any given location on Earth will shift completely outside the limits of historical precedents, defining that year as the year of climate departure.
The data came from 39 Earth System Models developed independently by 21 climate centers in 12 different countries.
The study has been published in the Nature.
--ANI (Posted on 10-10-2013)