I have a raster layer (.tif) that represents mixed layer depth in the Eastern pacific (it has no attribute table). I also have a feature class point layer showing the spotted and spinner dolphin sets (the place where a dolphin set occurred by the tuna fishery). The number of sets per year is approx. 15,000 events. Is there a way to join the two layers so that when looking at the dolphin set attribute table I can see the spatial connection to what depth the set occurred? I can do this manually -- by zooming in on each set point and using the identify tool, click the oceanography layer, to tell me mixed layer depth -- but my dataset is huge, and I need to do this for each year, and season, over a 25 year period, and I don't have time to do this. If I'm able to tell at what depth each set occurred, I can then average them, and find at what depth spinner sets are occurring, and at what depth spotted sets are occurring, for each year, and compare how this has changed over the 25 year period. Does anyone have any suggestions, or ways I may be able to get around this issue? Thank you!
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I need help! I'm working with an ocean raster data set that covers the Eastern Tropical Pacific region. I'm trying to calculate the area of different depth classes. I have the raster classified into three depth classes using the reclassify tool, and have the counts for each class. The pixel size is 0.5 by 0.5, and the map unit is decimal degrees. The coordinate system I'm using is WGS 1984. I know converting decimal degrees to meters is fairly arbitrary because longitude changes at different latitudes, but I'm trying to get a rough estimate any way. The area is right above the equator, so I'm thinking lat and long should both be close to 111km^2. The area calculations I'm getting seem wayyyy off however, as the entire region should be close to 3.5 million square miles, and when I add all the areas together I'm getting roughly 430,000km squared. My 0-20m depth class has a count of 852. When I take the cell value (0.5x0.5) and multiply it by 852 (so .25 x 852) and then multiply that by 111km^2, I'm getting 23,463km^2. Am I doing something wrong? Can someone suggest another method or correct me I'm doing this calculation incorrectly?
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