SOFIE conducts solar occultation measurements at 16 wavelengths (spectral bands) that are used to retrieve vertical profiles of temperature, O3, H2O, CO2, CH4, NO, and extinction due to PMCs and meteoric smoke at multiple wavelengths from 0.330 to 5.006 mm [Gordley et al., 2009]. SOFIE performs 15 sunset and 15 sunrise measurements each day. The measurements offer high sensitivity due to the long atmospheric path length (~300 km) combined with the bright solar source and a precise electro-optical system. SOFIE provides ~1.6-km vertical resolution and the high precision allows retrievals on the over-sampled 200 m vertical grid. Multi-wavelength extinction measurements are used to determine an unprecedented variety of physical PMC properties including ice volume density, ice water content, particle shape, ice concentration and size, ice particle temperature, and the amount of meteoric smoke contained in ice [Hervig et al., 2009; Hervig and Gordley, 2010; Hervig et al., 2012]. SOFIE made the first observations of meteor smoke from satellite [Hervig et al., 2009], which were most recently used to determine the chemical composition of meteoric smoke, and provide a new estimate of the meteoric influx into Earth\'s atmosphere [Hervig et al., 2017b].
Data Product Overview
L0 consists of the raw measurements, including detector response (counts), sun sensor output (solar edge locations), and housekeeping data. L0 is available to plot online, primarily for instrument diagnostics.
L1 contains the measurements after processing to account for instrument characteristics such as electronics (e.g. multiplexing), calibration (e.g., detector response non-linearity), registration in altitude, and interpolation of all signals to a uniform altitude grid. L1 is available to plot online, primarily for instrument and algorithm diagnostics.
L2 files contain vertical profiles of all retrieved products (e.g., temperature, gas mixing ratios, aerosol extinction) for one day. Gas retrievals (e.g., H2O) are reported in terms of volume mixing ratios (VMR), which is the volume of a gas per unit volume of air. The aerosol extinctions are reported in units of 1/km. This is a convenient reduction of the baseline parameter which is the optical cross section (length squared) per unit volume of air (length cubed). The files also include ancillary information such as date, time, latitude, and longitude for each event. SOFIE typically observes 15 sunset and 15 sunrise events per day (30 events per day). L2 can be plotted online, or downloaded as NetCDF files.
Mission Files (derived from Level 2)
Mission files have one retrieval product (e.g., CH4) for the whole mission, and contain both sunrise and sunset events. The IDL reader below has an option to return all events or just sunrise/sunset events. The file name contains the date range (YYYYDOY) and the species for that file. The NetCDF files are updated periodically to include the latest data.
The L3 product consists of longitude versus altitude cross section plots, for each day and in each hemisphere (2 plots per day). L3 plots can be viewed and/or downloaded online.
Level 4, also known as PMC Summary Files
SOFIE summary files contain data for each PMC season. The files include vertical profiles of temperature, pressure, gas mixing ratios, and PMC extinctions. A variety of retrieved PMC properties are in the files including ice layer top, peak, and bottom altitudes, ice mass and volume density, the gas phase equivalent H2O contained in ice, ice particle shape, ice temperature, Gaussian size distribution parameters, IWC, and vertical optical depths. The NetCDF files are available for download.
Gravity Wave Files
Gravity waves (GW) are characterized through the analysis of SOFIE temperature profiles, as described by Thurairajah et al. . Vertical profiles of GW potential energy and amplitude are reported, with results for each hemisphere in separate NetCDF files. Please see the GW description document on the GW page for details (readme_sofie_gws_v0.0.pdf). The SOFIE GW products were provided by Dr. Brentha Thurairajah (email@example.com). The NetCDF files are available for download.
Event Date & Location
These files contain the SOFIE event number, orbit, date, UT Time, latitude, and longitude for each event. This is useful for locating coincidences, or sampling model output. The ascii files are available for download.
Gordley, L. L., M. Hervig, C. Fish, J. M. Russell III, S. Bailey, J. Cook, S. Hansen, A. Shumway, G. Paxton, L. Deaver, T. Marshall, J. Burton, B. Magill, C. Brown, E. Thompson, and J. Kemp (2009), The Solar Occultation For Ice Experiment (SOFIE), J. Atmos. Solar-Terr. Phys., 71, 300-315, doi:10.1016/j.jastp.2008.07.012.
Hervig, M. E., L. E. Deaver, C. G. Bardeen, J. M. Russell, S. M. Bailey, and L. L. Gordley (2012), The content and composition of meteoric smoke in mesospheric ice particles from SOFIE observations, J. Atmos. Solar-Terr. Phys., doi:10.1016/j.jastp.2012.04.005.
Hervig, M. E., and L. L. Gordley (2010), The temperature, shape, and phase of mesospheric ice from SOFIE observations, J. Geophys. Res., 115, D15208, doi:10.1029/2010JD013918.
Hervig, M. E., L. L. Gordley, L. E. Deaver, D. E. Siskind, M. H. Stevens, J. M. Russell III, S. M. Bailey, L. Megner, and C. G. Bardeen (2009), First satellite observations of meteoric smoke in the middle atmosphere, Geophys. Res. Letters, doi:10.1029/2009GL039737.
Hervig, M.E., L.L. Gordley, M. Stevens, J.M. Russell, S. Bailey, and G. Baumgarten (2009), Interpretation of SOFIE PMC measurements: Cloud identification and derivation of mass density, particle shape, and particle size, J. Atmos. Solar-Terr. Phys., 71, 316-330, doi:10.1016/j.jastp.2008.07.009.