Satellite observation of atmospheric dust

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1 Satellite observation of atmospheric dust Taichu Y. Tanaka Meteorological Research Institute, Japan Meteorological Agency 11 April 2017, SDS WAS: Dust observation and Geneva

2 Dust observations by satellite Satellite observations are powerful tools for monitoring and data assimilation of atmospheric dust. Pros Wide coverage of horizontal area Enable observations where human observer can go/maintain High temporal resolution (geostationary) Cons Cannot observe dust under clouds Uncertainties in retrievals: quantitative observations are still difficult Especially over grounds with high reflectance (e.g., deserts!) requires validations with ground observations!

3 Earth observing satellites: categorize by orbits Low Earth Orbit (LEO) Polar/no polar orbit Sun synchronous/non sun synchronous Geostationary Image from education.psu.edu/eme810/node/477 Spatial resolution Low Earth Orbit (Polar orbit) High (MODIS: km) Geostationary Low* (*Himawari 8: 0.5 2km) Temporal resolution Low High Area coverage Global Localized disk

4 Low Earth orbit satellites Terra MODIS (MODerate resolution Imaging Spectroradiometer) MISR (Multi angle Imaging Spectro Radiometer) Aqua MODIS (MODerate resolution Imaging Spectroradiometer) AIRS (Atmospheric Infrared Sounder) CALIPSO CALIOP (Cloud Aerosol Lidar with Orthogonal Polarization) Aura OMI (Ozone Monitoring Instrument) PARASOL POLDER (Polarization and Directionality of the Earth's Reflectances) Suomi NPP VIIRS (Visible Infrared Imaging Radiometer Suite) OMPS (Ozone Mapping and Profiler Suite) MetOp ( A/B) GOME 2 AVHRR/3 PMAp A Train Upcoming: GCOM C: SGLI EarthCARE: ATLID, MSI JPSS series MetOp C

5 Geostationary Satellites Meteosat (EUMETSAT) SEVIRI (Spinning Enhanced Visible and InfraRed Imager) Now: MSG (Meteosat Second Generation): Next gen. MTG Himawari 8/9 (JMA) AHI (Advanced Himawari Imager): 16 spectral bands GOES (NOAA) Next generation: GOES 16 with ABI (Advanced Baseline Imager) will be operational: 16 spectral bands FY 2/4 (CMA) Next generation: FY 4A: AGRI (Advanced Geostationary Radiation Imager) will be operational: 14 spectral bands

6 Next generation geostationary satellites Specs: Multi spectral : ~ 16 bands Horizontal : 500m ~ 2 km Full disk scan: ~ 10min, Regional rapid scan: ~2.5 min Long operational periods: ~15 years Himawari 8 True Color reproduction Suitable for aerosol observation! Upcoming: GOES 16(/17), FY 4 series, Meteosat Third Generation

7 Dust observations: Categorization by sensor type products used for dust Wavelengths Imager Horizontal Dust RGB Aerosol Optical Depth (AOD) Angstrom Exponent DEBRA Dust Infrared Difference Dust Index (IDDI) Absorbing Aerosol Index (OMI, OMPS) Dust score (by AIRS) Ultraviolet to infrared (depends on the sensor) Lidar Vertical Aerosol extinction Attenuated backscatter Depolarization ratio Limited to specific laser bands (typically, 355/532/1064nm) Satellite orbit Any Low earth orbit only

8 Dust RGB image EUMETSAT algorithm to identify airborne dust Exploits the difference in emissivity of dust/desert surfaces, temperature difference of desert surface(hot) and the dust cloud (cooler). Pink to magenta colors indicate the presence of dust Available during day and nighttime Rather qualitative yet effective to monitor the evolution of dust storms From SDS WAS NA ME E website

9 Real Time Image of Himawari 8 User s Guide to RGB composite image is available. Select Dust RGB

10 Dust storm traveling over Mongolia and China, March 2016 by Himawari 8 DustRGB. The 10 minute interval movie of DustRGB captured the evolution of dust storm clearly.

11 Dust Plume over Desert Southwest, U.S. by GOES 16 (2017/03/24) Dust RGB with GOES 16 NOAA, From YouTube Dust Plume over Desert Southwest

12 Aerosol Optical Depth Quantitative value of the total aerosol (not only dust) in the atmospheric column Used for aerosol monitoring and data assimilation Dust detection may be difficult (but can be guessed from fine and coarse mode AOD) Available during daytime only (most cases)

13 Currently available AOD products MODIS (Collection 6) Long period: 2002 Most widely used for monitoring and data assimilation PMAp VIIRS AOD SEVIRI dust AOD (MSGAOD) Himawari 8 aerosol product Coming next generation geostationary satellites (GOES 16, FY 4A, MTG) are expected to provide aerosol products

14 MODIS AOD (NASA Worldview)

15 Himawari 8 Aerosol product by JAXA EORC JAXA EORC provides aerosol retrieval products of Himawari 8. (available in netcdf format)

16 Satellite Lidar observation Vertical profile of aerosol extinction and depolarization Used for aerosol monitoring and data assimilation research Depolarization ratio can be used to distinguish non spherical particles dust, volcanic ash From Used for data assimilation on research base Available during daytime and nighttime (daytime may be noisy)

17 3 D structure of dust transport captured by CALIOP (Yumimoto et al. 2009, ACP)

18 Space lidar platform Currently available CALIOP on CALIPSO product End of lifetime is approaching CATS on International Space Station (ISS) Future ATLID on EarthCARE (late 2018?)

19 DEBRA dust Other dust indices A New multi spectral satellite algorithm that utilizes ancillary surface data (SDS WAS NA ME E node website) Absorbing Aerosol Index (OMI, OMPS) Logarithmic difference between observed and pure Rayleigh atmosphere in a UV band. Indicates the presence of light absorbing aerosols (dust or black carbon) Infrared Difference Dust Index From overunited kingdom Dust detection from difference of infrared channels

20 Useful resources of satellite observation of atmospheric dust SDS WAS NA ME E Regional Center was.aemet.es/forecast products/dust observations SDS WAS Asia Regional Center NASA worldview Goddard Earth Sciences Data and Information Service Center (GES DISC) JAXA Himawari Monitor: Meteorological Satellite Center of JMA The Regional and Mesoscale Meteorology Branch (RAMMB) of NOAA/NESDIS EUMETSAT

21 Specification of Himawari 8/9 Imager (AHI) MTSAT 1R/2 VIS: 1km, IR: 4km AHI = Advanced Himawari Imager Band Wavelength [μm] Spatial Resolution VIS Km Km Km Km RGB band Composited True Color Image IR4 IR3 IR1 IR Km Km Km Km Km Km Km Km Km Km Km Km NIR SO2 O 3 CO2 Similar to ABI for GOES R, but 0.51 μm(band 2) instead of ABI s 1.38 μm Water vapor Atmospheric Windows Products Volcanic Ash Global Instability Index Nowcasting Typhoon Analysis Atmospheric Motion Vector Clear Sky Radiance Sea Surface Temperature Yellow Sands Snow and Ice Coverage

22 Airflow brings Sahara dust to the UK (2017/03/24 25) MetOffice, From YouTube Airflow brings Sahara dust to the UK