LIS/OTD Gridded Lightning Climatology Data Sets

Table of Contents

Introduction

The LIS/OTD Gridded Climatology data sets consist of gridded climatologies of total lightning flash rates seen by the spaceborne Optical Transient Detector (OTD) and Lightning Imaging Sensor (LIS). The long LIS (equatorward of about 38 degree) record makes the merged climatology most robust in the tropics and subtropics, while the high latitude data is entirely from OTD. The gridded climatologies include annual mean flash rate on a 0.5 degree grid, mean diurnal cycle of flash rate on a 2.5 degree grid with 24 hour resolution, mean annual cycle of flash rate on a 0.5 degree or 2.5 degree grid with daily, monthly, or seasonal resolution, mean annual cycle of the diurnal cycle on a 2.5 degree grid with two hour resolution for each day, and time series of flash rate over the entire record with roughly three-month smoothing. For some of these (e.g., annual cycle of the diurnal cycle), more smoothing is necessary for results to be robust. These data sets are described in the following paper: Gridded lightning climatology from TRMM-LIS and OTD: Dataset description

The LIS and OTD sensors monitor the 777.4 nm atomic oxygen multiplet, detecting pulses of illumination (produced by lightning) above background levels. Both are/were onboard satellites in low earth orbit, viewing an earth location for about 3 minutes as OTD passed overhead or 1.5 minutes as LIS passed overhead. Data files from each individual orbit are available from the Global Hydrology Resource Center (GHRC DAAC), with 14 orbits per day for OTD and 16 orbits per day for LIS. Lightning flash times and locations are recorded with approximately 10 km resolution from OTD and 5 km resolution from LIS. For a 0.5 degree x 0.5 degree latitude-longitude grid, the orbit files also record which grid boxes are within the field of view with the instrument collecting data properly (i.e., quality control flags indicate acceptable conditions) individually for each second of the orbit. Many other lightning attributes and instrument information are included in the orbital files (for example, flash duration, radiance, and areal extent of the illumination).

For each grid box, the total viewtime (observation duration) and flash count are summed over all orbits, and sorted by time of day and day of year.  Flash counts are scaled by each instrument’s detection efficiency which varies with time of day.  For the OTD,  detection efficiency also varies with geographic location.  The optical sensors can more easily discriminate lightning from the background scene at night, with bright daytime cloud tops being more difficult.  The LIS detection efficiency ranges from about 69% near local noon to 88% overnight.  Different sensitivity thresholds were used with the OTD during the course of its mission, with the detection efficiency adjusted accordingly. The OTD detection efficiency is reduced roughly in half over the South Atlantic Anomaly.  The detection efficiency values as a function of sensitivity thresholds, geographic location, and time of day are available in the data files for the gridded climatology. 

There are 10 Gridded Lightning Climatology data sets available. They are described in detail in the Gridded lightning climatology from TRMM-LIS and OTD: Dataset description and summarized in Table 1 below.

Table 1.  Products in LIS-OTD gridded climatology files.

The LIS/OTD Gridded Climatology data files are in Hierarchical Data Format (HDF). Information about HDF can be obtained from The HDF Group.

Sample reader code is available at:

LIS/OTD Climatology Data Reader Code
LIS/OTD Climatology Grid Reader Code

The LIS/OTD Gridded Climatology file naming convention is as follows:

Data: LISOTD_nnnn_Vx.x.yyyy.hdf
Browse: nnnn_COM_FR_Vx.x.yyyy.png
Animation: nnnn_COM_FR_Vx.x.yyyy.mov

where nnnn is the acronym for dataset (HRFC, HRAC, HRMC, LRFC, LRAC, LRDC, LRADC, LRTS, LRACTS, LRMTS)
Vx.x.yyyy is the version number

Our data sets are provided through the NASA Earth Science Data and Information System (ESDIS) Project and the Global Hydrology Resource Center (GHRC) Distributed Active Archive Center (DAAC). GHRC DAAC is one of NASA's Earth Observing System Data and Information System (EOSDIS) data centers that are part of the ESDIS project. ESDIS data are not copyrighted; however, in the event that you publish our data or results derived by using our data, we request that you include an acknowledgment within the text of the article and a citation on your reference list. Examples for general acknowledgments, data set citation in a reference listing, and crediting online web images and information can be found at: http://ghrc.nsstc.nasa.gov/uso/citation.html

References

Adler, R. F., J.-J. Wang, G. Gu, and G. J. Huffman: A Ten-Year Tropical Rainfall Climatology Based on a Composite of TRMM products. J. Meteor. Soc. Japan, 87A, 281-293, 2009.

Albrecht, R. and co-authors: The 13 years of TRMM Lightning Imaging Sensor: From Individual Flash Characteristics to Decadal Tendencies.  XIV Int. Conf. Atmos. Elec., Rio de Janeiro, Brazil, 2011.

Blakeslee, R. J., D. M. Mach, M. G. Bateman, and J. C. Bailey: Seasonal Variations in the Lightning Diurnal Cycle and Implications for the Global Electric Circuit. Atmos. Res., submitted, 2012.

Boccippio, D. J., W. J. Koshak, and R. J. Blakeslee: Performance Assessment of the Optical Transient Detector and Lightning Imaging Sensor, I, Predicted Diurnal Variability, J. Atmos. Oceanic Technol., 19, 1318-1332, 2002.

Brooks, C. E. P., The Distribution of Thunderstorms Over the Globe, Geophys. Memo., 3(24), 147– 164, 1925.

Bürgesser, R.E., M.G. Nicora, and E.E. Ávila: Characterization of the Lightning Activity of “Relámpago del Catatumbo”. J. Atmos. Solar-Terr. Physics, doi:10.1016/j.jastp.2012.01.013, 2012.

Cecil, D. J. and C. B. Blankenship: Toward a Global Climatology of Severe Hailstorms as Estimated by Satellite Passive Microwave Imagers, J. Clim., 25, 687-703, 2012.

Cecil, D.J, D.E. Buechler, and R.J. Blakeslee, 2012: Gridded lightning climatology from TRMM-LIS and OTD: Dataset description.  Atmos. Res., 10.1016/j.atmosres.2012.06.028.

Christian, H. J. and co-authors: Global Frequency and Distribution of Lightning as Observed from Space by the Optical Transient Detector, J. Geophys. Res., 108(D1), 4005, doi :10.1029/2002JD002347, 2003.

Hernandez, C. A. and C. Schumacher : The QBO’s Influence on Lightning Production in the Tropics. 28th Conf. On Hurricanes and Trop. Meteor., Amer. Meteor. Soc., Orlando, FL, 2008.

Kummerow, C. and co-authors : The Status of the Tropical Rainfall Measuring Mission after 2 years in Orbit. J. Appl. Meteor., 39, 1965-1982, 2000.

Mackerras, D., M. Darveniza, R. E. Orville, E. R. Williams, and S. J. Goodman, Global lightning: Total, Cloud and Ground Flash Estimates, J. Geophys. Res., 103(D16), 19,791–19,809, doi:10.1029/98JD01461, 1998.

Orville, R. E., and D. W. Spencer, Global Lightning Flash Frequency, Mon. Weather Rev., 107, 934– 943, 1979.

To order these data or for further information, please contact:

Global Hydrology Resource Center
User Services
320 Sparkman Drive
Huntsville, AL 35805
Phone: 256-961-7932
E-mail: support-ghrc@earthdata.nasa.gov
Web: http://ghrc.nsstc.nasa.gov/