What Can we Learn from SALTRACE for Future Earth Explorer Missions?
Weinzierl, Bernadett¹; Sauer, Daniel²; Reitebuch, Oliver¹; Groß, Silke¹; Minikin, Andreas¹; Dörnbrack, Andreas¹; Schäfler, Andreas¹; Kox, Stephan¹; Graf, Kaspar¹; Gasteiger, Josef³; Freudenthaler, Volker⁴; Ansmann, Albert⁵; Althausen, Dietrich⁵; Rapp, Markus^1
1Deutsches Zentrum für Luft- und Raumfahrt (DLR), GERMANY; ²Meteorologisches Institut, Ludwig-Maximilians-Universität (LMU) München, GERMANY; ³Meteorologisches Institut, Ludwig-Maximilians-Universität (LMU), München, GERMANY; ⁴Meteorologisches Institut, Ludwig-Maximilians-Universität (LMU), GERMANY; ⁵Leibniz Institute for Tropospheric Research (Tropos), Leipzig, GERMANY

To understand climate change and allow meaningful predictions of the future climate, the uncertainty in our understanding of atmospheric aerosol particles and their role in the Earth system must be reduced. With the Earth Clouds, Aerosols and Radiation Explorer mission EarthCARE scheduled for 2015 a new era in assessing aerosol-cloud interactions will start. Aside from other instruments, EarthCARE will be equipped with a high spectral resolution lidar (HSRL) operating at 355 nm. For EarthCARE, a number of geophysical products such as aerosol type classification will be provided, but these products need to be validated with data from in-situ measurements of atmospheric aerosol layers at different altitudes and from alterative remote sensing approaches.

In this presentation, we will discuss how data from field experiments such as the Saharan Aerosol Long-range Transport and Aerosol-Cloud-Interaction Experiment (SALTRACE) can be used to validate EarthCARE measurements.

SALTRACE is a German initiative which combines ground-based and airborne in-situ and lidar measurements with meteorological data, long-term measurements, satellite remote sensing and modeling to investigate the long-range transport of Saharan mineral dust across the Atlantic Ocean into the Caribbean. SALTRACE continues the work started with SAMUM (Saharan Mineral dust Experiment) and will help to close open gaps in our understanding of mineral dust in the climate system. Within SALTRACE, an aircraft field experiment involving the DLR Falcon research aircraft will be conducted in June/July 2013 in the Cape Verde area and in the Caribbean. The DLR Falcon research aircraft will be equipped with an extensive set of aerosol in-situ instruments for size, volatility, and absorption measurements, impactor sampling for chemical analyses and with a nadir-looking 2-μm wind lidar system providing data of mineral dust and other aerosol layers.

In our presentation, we give an overview of SALTRACE and present first results of this study. We will combine data from airborne and ground-based lidar with airborne in-situ measurements to show how data from a field experiment like SALTRACE can be used as EarthCARE validation products for retrieved aerosol microphysical properties. Presented results will cover profiles of dust size distributions and dust optical properties. In addition, the microphysical properties of mineral dust measured during SAMUM-1, SAMUM-2 and SALTRACE will be compared. It will be discussed to which extent changes in microphysical aerosol parameters are reflected in the optical parameters of the lidar measurements. Furthermore, we will discuss to what extent lidar measurements of particle linear depolarization and lidar ratio at 355 nm can be used for aerosol classification.