Computer models can fill in the blanks left by satellite remote sensing and in-situ measurements. Scientists at the University of Montana produced this animation of daily net primary productivity (carbon uptake by plants) from model results. Green represents carbon being consumed by vegetation (positive productivity), while tan shades are carbon being released back into the atmosphere (negative productivity). Sensor: No Satellite/ No Data. Data Start Date: 1/1/84. Data End Date: 12/31/84.