Distribution of National Lightning Detection Network (NLDN) data is  restricted to INTEX NASA/EOS 
researchers and collaborators only. These  data are provided to INTEX via the Marshall Space Flight 
Center Lightning  Investigation Group by contract with the data producer Vaisala, Inc.  These data are
 NOT to be released to anyone other than authorized INTEX  NASA/EOS investigators and collaborators. 
Due to the wording of the  contract with Vaisala, should these data become available to unauthorized  
individuals the data stream may be terminated. Thus, it is very important  that only INTEX NASA/EOS 
investigators and collaborators be provided  access to the NLDN data. Should you have further 
questions, contact the  Global Hydrology Resource Center (GHRC) at  ghrc@eos.nasa.gov  

  While detection efficiency for the NLDN is 90% or better over  the continental U.S., it drops off 
rapidly outside the US borders  and off the coast (goes to zero at ~1000 km). The detection efficiency 
for the LR data is not well characterized, but is definitely less  than that achieved by the NLDN over 
the US and approaches zero at  distances in the 1500 - 2500 km range from US border or coastline.
  
  The data are collected by a private company and are provided to NASA for  Earth Science research. 
An acknowledgement must be given in any work  published using these data. A suggested text follows: 
"The National  Lightning Detection Network data were collected by Vaisala-Thunderstorm  and supplied 
to us by the Global Hydrology Resource Center at NASA  Marshall Space Flight Center".