19/01- Charla: "The Atacama Surface Solar Maximum"


Seminars and Colloquia at ESO/Santiago

Nuestro investigador, Roberto Rondanelli dictará la Charla: «The Atacama Surface Solar Maximum» el Lunes 19.01.15 a las 12:00

ESO Vitacura
Alonso de Córdova 3107
Santiago de Chile

Más información: http://www.eso.org/sci/meetings/santiago.html


Solar radiation reaching the earth’s surface is one of the major drivers of climate dynamics. By setting the surface energy balance, downwelling solar radiation indirectly heats the atmosphere and controls the hydrological cycle. Besides its critical importance as a physical mechanism for driving climate and weather, solar radiation has attracted interest as a potentially major source of energy for human activities. 
For a given latitude, solar radiation at the earth’s surface depends mostly on the composition along the atmospheric path. Since the early 20th century major astronomical observatories have led the search for the best places for observation from the earth, which presents a similar problem to the one of finding the maximum of solar radiation at the surface. In particular, Mount Montezuma in the Atacama desert, Chile, was identified by the pioneers of solar observation as an ideal place to conduct the search for variations of the solar constant estimated from the earth’s surface. 
By using available global datasets, a semi-empirical model for the surface solar radiation over Northern Chile and a network of surface stations, we confirm Atacama as the place where the highest mean surface solar radiation is found. The most likely location of the maximum downwelling solar radiation over the surface of the planet is on the pre-Andean Domeyko cordillera (3500 to 5000 m above the mean sea level, between 24 to 25 °S, along 69 °W) with a value of about 310 ± 15 W/m2. We discuss the main regional and local features of this region that conspire to produce the solar maximum. 
I will also discuss some elements of future trends in atmospheric opacity on the basis of climate scenarios from the CMIP-5 latest IPCC report. 
Article for reference: http://journals.ametsoc.org/doi/abs/10.1175/BAMS-D-13-00175.1