[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[GEMPAK #NKR-852146]: Count NLDN lightning strikes wtihin a given radius of a point?

This archive contains answers to questions sent to Unidata support through mid-2025. Note that the archive is no longer being updated. We provide the archive for reference; many of the answers presented here remain technically correct, even if somewhat outdated. For the most up-to-date information on the use of NSF Unidata software and data services, please consult the Software Documentation first.

  • Subject: [GEMPAK #NKR-852146]: Count NLDN lightning strikes wtihin a given radius of a point?
  • Date: Fri, 15 Jun 2007 10:18:26 -0600
> Hi,
> 
> 
> 
> I'm a graduate student at Plymouth State University.  The goal of my
> research is to develop a 10-year thunderstorm climatology across northern
> New England.  I'd like to incorporate both radar and nldn cloud to ground
> lightning data.
> 
> 
> 
> Currently, I'm doing a test run for the warm-season (Apr-Sep) 2005.
> Possible thunderstorms are first identified using the radar data.  Each
> possible thunderstorm has a datetime, latitude, and longitude.  In order to
> know whether a radar indicated cell is actually a thunderstorm, I'd like to
> search for lightning within a radius of ~10km from each cell.  All the raw
> nldn files were successfully converted into GEMPAK (.gem) surface files
> using this command in a .csh script:
> 
> 
> 
> dcnldn -v 1 -m 25000 -s minute05 -d /home2/emlowery/research/logs/dcnldn.log
> /home2/emlowery/research/nldn/2005_raw/{yr}{mo}{dy}{hr}.nldn
> 
> 
> 
> Is there a gempak program which can count the number lightning strikes
> within a given radius of a point (lat/lon)?



Evan,

Yes, I provide a program in the GEMPAK distribution called GDOBSCNT which
counts the number of observations in a user defined radius of points within
a grid file at a given time.

For convenience, I store the lightning data into data bins of 5 minutes, but 
GEMPAK date/time format can be as little as 1 minute. 

Steve Chiswell
Unidata User Support

> 
> 
> 
> Sincerely,
> 
> Evan Lowery
> 
> 
> 
> 
> 
> -----------------------------------------
> 
> Evan Lowery
> 
> Applied Meteorology M.S. Program
> 
> Plymouth State University
> 
> Boyd Hall 238
> 
> (215)534-6908
> 
> <http://vortex.plymouth.edu/~emlowery> http://vortex.plymouth.edu/~emlowery
> 
> Mirror:  <http://www.evanlowery.com/> http://www.evanlowery.com
> 
> <mailto:address@hidden> address@hidden
> 
> 
> 
> 
> 


Ticket Details
===================
Ticket ID: NKR-852146
Department: Support GEMPAK
Priority: Normal
Status: Closed