Improving the Representation of the Vertical Temperature through a Modified Cubic Spline Interpolation Scheme

Tuesday, 16 December 2014
Rosalyn F MacCracken, R. James Purser and Andrew Collard, I.M. Systems Group@NCEP/NWS/EMC, College Park, MD, United States
In the effort to reduce errors, and improve the accuracy of the representation of the vertical profile of temperature, a new “modified cubic spline” interpolation scheme is being tested for use within the Gridded Statistical Interpolation (GSI), within the Global Forecast System. This scheme differs from the existing horizontal and vertical linear interpolation scheme, since it utilizes additional target points to create a smoother profile. Through comparison testing with existing methodologies, it has been determined that better representation at the tropopause has been achieved in several test cases, and in within various zonal global regions. This poster illustrates the implementation of the new interpolation scheme, and the comparison to the existing methodologies.