1. MEIDEX – MEDITERRANEAN ISRAELI DUST EXPERIMENT - A SPACE, AIR AND GROUND BASED STUDY OF DESERT AEROSOL Z. Levin, J. Joseph, Y. Mekler, P. Israelevich, E. Ganor, Y. Yair, A. Devir, E. Klodzh, I. Koren, M. Mualem, Y. Noter, D. Shtivelman, A. Teller Department of Geophysics and Planetary Sciences, Tel Aviv University, Ramat Aviv, Israel First Israeli astronaut flight Under an agreement between NASA and ISA (Israeli Space Agency) An experiment on board the shuttle within the Hitchhiker program WHY STUDY DUST STORMS? Desert dust particles are a major component of natural aerosols in the atmosphere They may help to cool or warm the atmosphere depending on their distribution, size and chemical composition They affect clouds and precipitation They are in the right particle size to affect our health being deposited in the lungs They affect mechanical systems (e.g. jet engines, helicopters etc.) They reduce the contrast in remote sensing measurements They affect biological activity in the Ocean Dust storm over the Dead Sea Desert dust particles Desert dust in Tel Aviv (3 pm)Distribution of Non-absorbing aerosols MEIDEX SCIENTIFIC OBJECTIVES DAYTIME PRIMARY EXPERIMENTS : Validate TOMS versus MODIS Sources, Transport, Sinks and Properties of Desert Aerosol over the Mediterranean and Atlantic Ocean Absolute calibration of TOMS and MODIS by ground and airborne measurements DAYTIME SECONDARY EXPERIMENTS: Spectral Sea Surface BRDF with emphasis on UV Construct Visual Slant Visibility Model NIGHT TIME EXPERIMENT (TERTIARY): Sprites, Elves and other related phenomena – correlation with ground measurements of electro-magnetic radiation and visual observations. The regions of interest General scheme of the experiment 1.Wing mounted optical spectrometers (0.1 to 3  m, and 0.3 to 47  m) 2.Isokinetic sampling of aerosol particles on filters and on electron microscope grids 3.Ram collection of large (>2.5  m) aerosols 4.Two albedometers 5.GPS 6.Temperature sensors Airborne Measurements Flight base: Crete, or Sardinia, or Tenerife Radius: 500 miles Observations of Sprites Sprite observation by XYBION camera will be carried our over South America and the Tropics) Simultaneous ground observations will be carried out by teams from a number of countries (Israel, USA, Germany, Brazil, Japan and Taiwan) Measurements of VLF waves (in particular Schumann resonance) from TAU Mitzpe Ramon station will be correlated with the space and ground observations Xybion IMC- 201 radiometric CCD camera CCD Sensor: 756Hx581V Sensitivity ≥10 -6 fc (~ 0.1 of typical night sky) Spectral range: 340-860nm 6 bands: 0.34, 0.38, 0.44, 0.56, 0.66, 0.86 nm Exposure Times: 50 nsec - 4 msec in 50 nsec steps Wide Field Of View - SEKAI White Light video camera Both cameras are mounted in a 1-axis gimbaled truss Gimbal angular range: ± 22.5 Degrees Scan direction: ± Y FOV Xybion: 16 o (68km at the altitude 256km - 100m/pix) FOV SEKAI: 60 o (270 km at the altitude 256 km) Dust forecast for daily planning Dust Forecast with the TAU_ETA model and TOMS observations for April 23, 2001 The data is transformed into a two-dimensional wavelet space with the cloud cluster and the dust cluster separated and orthogonal. Chemical analysis and size distribution of dust samples Chemical spectra of dust particles (<10  m) sampled before, during and after severe dust storm April 14- 22, 2000, at Tel Aviv Spaceborne Measurements Dust and Clouds Detection Input image – SeaWiFS – Saharan Dust Storm 28-02-2000 Classification (wavelets) Red - Clouds, Green - Ocean, Blue - Dust Original image filtered by the mask http://www.tau.ac.il/geophysics/MEIDEX/home.htm Comparison between aerosol volume distributions during and after dust storm, April 21, 2001, at Tel Aviv Upper End Plate w/ Quartz Window Gimbal Motor & Worm Drive Worm Gear SEKAI WFOV Camera Lower End Plate Lens & Baffle Xybion Camera Avionics Mount Plate w/ electronics Overall MEIDEX configuration