Strong Saharan Dust Event Detected at Lalinet LOA-UNAL Station, over Medellín, Colombia by Active and Passive Remote Sensing

Andrés Bedoya,Jose F Jiménez,Álvaro Bastidas,Dairo Alegría,Carmen E Zapata,Mauricio Múnera,Daniel Nisperuza,Eduardo Landulfo,Juan Luis Guerrero-Rascado,B Gross,M Arend,F Moshary

doi:10.1051/epjconf/201611908006

Abstract

Passive and active remote sensing techniques are well used for understanding optical and microphysical characteristics of aerosol layers. Lidar has the ability to resolve stratifications of the complex vertical structures in the atmosphere and determine the existence of aerosols which has been transported for long-ranges through the evaluation of the optical properties such as particle backscatter and extinction coefficients, among others. CIMEL sunphotometer data (AERONET network) give information about optical properties such as Aerosol Optical Depth (AOD), Single Scattering Albedo (SSA), and Angstrom Exponent (AE) and microphysical properties such as size distribution. The LOA-UNAL lidar station as part of the LALINET (Latin American LIdar NETwork) [1], involves an elastic coaxial system operating in zenith mode used for monitoring the atmosphere at Medellin-Colombia (6.26°N, 75.58°W, 1470 m asl). This work presents a Saharan dust even over Medellin, Colombia, 27 th June, 2014, observed simultaneously with lidar, sun-photometer and complementary global mass transport model HYSPLIT.

Highlights

Anthropogenic and natural radiative forcing is a very important topic which has many uncertainties
Mineral dust aerosols from North Africa represent one of the largest sources of aerosols available to the atmosphere, and their generation and transport are thought to be modulated by African easterly waves
We report an event of dust particles advected over Medellín city in Colombia, see figure 1, which was registered by first time in this region, using remote sensing instrumentation: lidar and sun-photometer

Summary

INTRODUCTION

Anthropogenic and natural radiative forcing is a very important topic which has many uncertainties (e.g. mineral dust particles). Sources of mineral dust particles on global scale are Sahara and Gobi deserts which are located on the African continent. Their principal effect is by scattering and absorption (direct effect), and their interaction with clouds (indirect effect) [3]. Mineral dust aerosols from North Africa represent one of the largest sources of aerosols available to the atmosphere, and their generation and transport are thought to be modulated by African easterly waves. The Sahara desert as the world’s most important dust source adjoins directly to the Atlantic Ocean.

RESULTS

METHODOLOGY

CONCLUSIONS