Changes in the surface irradiance during the total solar eclipse 2020 in Valcheta, Argentina

ORTE, PABLO FACUNDO; FERNÁNDEZ LAJÚS, EDUARDO; DI SISTO, ROMINA P.; WOLFRAM, ELIAN A.; LUSI, ANABELA R.; NICORA, M. GABRIELA; D'ELIA, RAÚL L.; VERSTRAETEN, FEDERICO; PAPANDREA, SEBASTIÁN; CARMONA, FACUNDO

Papers in Physics

Papers in Physics

Año: 2023 vol. 15

On December 14, 2020, southern South America experienced a total solar eclipseclose to the solar noon. The path of totality, about 90 km wide, extended overthe continental region from the Chilean west coast to the Argentine east coast,passing through the provinces of Neuqu´en, R´ıo Negro and the extreme south ofBuenos Aires. In order to study the effects on the atmosphere produced by thetotal eclipse, the Servicio Meteorol´ogico Nacional Argentino (SMN) and Institutode Investigaciones Cient´ıficas y T´ecnicas para la Defensa (CITEDEF) carried out asurface radiometric monitoring campaign in Valcheta (40.69°S; 66.15°W), R´ıo Negro, Argentina. In this work, we explore the global surface solar irradiance on ahorizontal plane (GHI) with the main objective of quantifying the changes in thisparameter for cloudy and clear sky atmospheric conditions, combining ground-basedmeasurements and modeling. A solar limb-darkening function was successfully implemented in the calculation of the irradiance at the top of the atmosphere (TOA)during the eclipse. We estimated a significant GHI attenuation of 41 % betweenthe first (C1) and last (C4) contacts of eclipse compared to similar atmosphericconditions without the total eclipse, which represent a daily reduction of 12 %. Interms of irradiation, a reduction of 3360.1 KJ/m2 was calculated.