1. 
   LWIR
   acronym: long-wavelength (thermal) infrared
   Found op http://cdiac.ornl.gov/pns/acronyms.html#L
   
   
2. 
   LWIR
   Long Wavelength Infra Red
   Found op http://www.e2v.com/assets/media/files/documents/imaging-space-and-scientifi
   
   
3. 
   lwir
   1) Long-wavelength infrared
   Found op http://www.mijnwoordenboek.nl/EN/crossword-dictionary/lwir/1
   
   

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