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>From: Jimmy Adegoke <address@hidden> >Organization: Penn State >Keywords: 199907292205.QAA14340 McIDAS Jimmy, >A search using NDVI and Arc/INFO as keywords on your website Q&A search >engine returned nil hence this e-mail. Two questions: > >1. I have NDVI images (derived from AVHRR level 1B data) which I use in >ERDAS and would like to bring into MCIDAS. The plan is to look at >NDVI-convective cloud associations in one software environment. >Characteristics of the NDVI data that I'm using include the following: > >Units: unitless >Data Range: -1 to +1 >Data type: 8 bits(unsigned) >Offset: 128 >Gain: .008 >Bin. min/max: 3/253 ># of colums/rows: 1090/820 > >Note: 8 bit data is scaled - so to obtain actual geophysical values one >has to subtract the offset from the scaled data value and multiply the >result by the gain. To put the data in a McIDAS AREA file format, the data will have to be scaled appropriately for the number of bytes used to represent the information (i.e. 0 - 255 for 1 byte, etc.). >2. I also do some GIS type work in Arc/INFO and was wondering if there are >utilities avalable to convert an ARC polygon or point coverage into a >format that McIDAS can read. Not that I know of. >The goal here is to look at surface (land >cover) influences on convective cloud initiation/dissipation. > >I can place samples NDVI composite image and ARC coverages in my outgoing >ftp directory for download if you require me to do so. I will not have time to look into this until after the McIDAS workshop finishes a week from Saturday. >Thanks for your help. See you at the workshop. >Jimmy Adegoke >Climate Program >Geog. Dept. & Earth System Sc.Center >302 Walker Building >The Pennsylvania State University >University Park PA 16802 > >e-mail: address@hidden >Fax: (814) 863-7943; Office Phone: (814) 865-6151 Tom Yoksas