<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">Hi All,<div>I need to calculate column water vapor from specific humidity. The way I have done this in the past is to use the grads function vint (just as in the example in the documentation). However, now I am using a data set that has a hybrid height coordinate with units in 'm' rather than pressure levels in 'mb'. Is there a way to use the vint function when the z levels aren't in mb? <div><br></div><div>If the vint function does not fit the situation, I was also looking into doing the integral layer by layer, but I am stuck on how to get the pressure information from the hybrid height coordinate. If anyone has some insights on these I would much appreciate it! </div><div><br></div><div>I've attached the file information (clipped from ncdump) with the vertical layer info of the data set (netcdf format, CMIP5 data, in this case: HadGEM2-ES model).<div><br></div><div>With Thanks,</div><div>Katrina</div><div><br></div><div>--------------------------------------------</div><div><div>netcdf hus_6hrLev_HadGEM2-ES_rcp45_r1i1p1_202512010600-202603010000 {</div><div>dimensions:</div><div> time = UNLIMITED ; // (360 currently)</div><div> lev = 38 ;</div><div> lat = 145 ;</div><div> lon = 192 ;</div><div> bnds = 2 ;</div><div>variables:</div><div> double time(time) ;</div><div> time:units = "days since 1859-12-01" ;</div><div> time:calendar = "360_day" ;</div><div> time:axis = "T" ;</div><div> time:long_name = "time" ;</div><div> time:standard_name = "time" ;</div><div> double lev(lev) ;</div><div> lev:bounds = "lev_bnds" ;</div><div> lev:units = "m" ;</div><div> lev:axis = "Z" ;</div><div> lev:positive = "up" ;</div><div> lev:long_name = "hybrid height coordinate" ;</div><div> lev:standard_name = "atmosphere_hybrid_height_coordinate" ;</div><div> lev:formula = "z(k,j,i) = a(k) + b(k)*orog(j,i)" ;</div><div> lev:formula_terms = "a: lev b: b orog: orog" ;</div><div> double lev_bnds(lev, bnds) ;</div><div> lev_bnds:formula = "z(k,j,i) = a(k) + b(k)*orog(j,i)" ;</div><div> lev_bnds:standard_name = "atmosphere_hybrid_height_coordinate" ;</div><div> lev_bnds:units = "m" ;</div><div> lev_bnds:formula_terms = "a: lev_bnds b: b_bnds orog: orog" ;</div><div> double b(lev) ;</div><div> b:long_name = "vertical coordinate formula term: b(k)" ;</div><div> float orog(lat, lon) ;</div><div><br></div><div>.....</div><div><br></div><div> lev = 20.000337600708, 80.001350402832, 179.999114990234, 320.00146484375, </div><div> 500.000579833984, 720.000366210938, 980.000854492188, 1279.998046875, </div><div> 1619.99987792969, 1999.99841308594, 2420.00170898438, 2880.00146484375, </div><div> 3379.99829101562, 3919.99951171875, 4500.00146484375, 5120, </div><div> 5779.99951171875, 6479.99951171875, 7220, 8000.00146484375, 8820, </div><div> 9679.9990234375, 10579.998046875, 11519.998046875, 12499.9990234375, </div><div> 13520.0009765625, 14580.7998046875, 15694.6396484375, 16875.310546875, </div><div> 18138.626953125, 19503.009765625, 20990.1875, 22626.08203125, </div><div> 24458.28515625, 26583.640625, 29219.080078125, 32908.69140625, </div><div> 39254.83203125 ;</div><div><br></div><div> lev_bnds =</div><div> 0, 49.9988822937012,</div><div> 49.9988822937012, 130.000228881836,</div><div> 130.000228881836, 249.998336791992,</div><div> 249.998336791992, 410.001037597656,</div><div> 410.001037597656, 610.00048828125,</div><div> 610.00048828125, 850.000610351562,</div><div> 850.000610351562, 1130.00146484375,</div><div> 1130.00146484375, 1449.9990234375,</div><div> 1449.9990234375, 1810.00109863281,</div><div> 1810.00109863281, 2210,</div><div> 2210, 2649.99951171875,</div><div> 2649.99951171875, 3129.99975585938,</div><div> 3129.99975585938, 3650.00073242188,</div><div> 3650.00073242188, 4209.99853515625,</div><div> 4209.99853515625, 4810.0009765625,</div><div> 4810.0009765625, 5450,</div><div> 5450, 6129.99951171875,</div><div> 6129.99951171875, 6850,</div><div> 6850, 7610.0009765625,</div><div> 7610.0009765625, 8409.9990234375,</div><div> 8409.9990234375, 9250.0009765625,</div><div> 9250.0009765625, 10130,</div><div> 10130, 11050,</div><div> 11050, 12010.0009765625,</div><div> 12010.0009765625, 13010.001953125,</div><div> 13010.001953125, 14050.400390625,</div><div> 14050.400390625, 15137.7197265625,</div><div> 15137.7197265625, 16284.9736328125,</div><div> 16284.9736328125, 17506.96875,</div><div> 17506.96875, 18820.8203125,</div><div> 18820.8203125, 20246.599609375,</div><div> 20246.599609375, 21808.13671875,</div><div> 21808.13671875, 23542.18359375,</div><div> 23542.18359375, 25520.9609375,</div><div> 25520.9609375, 27901.357421875,</div><div> 27901.357421875, 31063.888671875,</div><div> 31063.888671875, 36081.76171875,</div><div> 36081.76171875, 42427.90234375 ;</div><div><br></div><div> b = 0.99771648645401, 0.990881502628326, 0.979542553424835, 0.9637770652771, </div><div> 0.943695485591888, 0.919438362121582, 0.891178011894226, </div><div> 0.859118342399597, 0.823493480682373, 0.784570515155792, </div><div> 0.742646217346191, 0.698050200939178, 0.651142716407776, </div><div> 0.602314412593842, 0.55198872089386, 0.500619947910309, 0.44869339466095, </div><div> 0.39672577381134, 0.34526526927948, 0.294891387224197, 0.24621507525444, </div><div> 0.199878215789795, 0.156554222106934, 0.116947874426842, </div><div> 0.0817952379584312, 0.0518637150526047, 0.0279368180781603, </div><div> 0.0107164792716503, 0.00130179093685001, 0, 0, 0, 0, 0, 0, 0, 0, 0 ;</div><div><br></div><div> orog =</div><div> 2801.479, 2801.479, 2801.479, 2801.479, 2801.479, 2801.479, 2801.479, </div><div>....</div><div><br></div><div>---------------------------------------------</div><div><br></div><div><br></div><div>
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<p style="margin: 0.0px 0.0px 0.0px 0.0px"><font face="Helvetica" size="4" style="font: 14.0px Helvetica">Katrina Hales-Garcia</font></p>
<p style="margin: 0.0px 0.0px 0.0px 0.0px"><font face="Helvetica" size="4" style="font: 14.0px Helvetica">UCLA Department of Atmospheric and Oceanic Sciences</font></p>
<p style="margin: 0.0px 0.0px 0.0px 0.0px"><font face="Helvetica" size="4" style="font: 14.0px Helvetica">7235 Math Sciences Bld.</font></p>
<p style="margin: 0.0px 0.0px 0.0px 0.0px"><font face="Helvetica" size="4" style="font: 14.0px Helvetica">Los Angeles CA<span class="Apple-converted-space"> </span>90095-1565</font></p><div><span class="Apple-style-span" style="font-size: 14px; ">hales at <a href="http://atmos.ucla.edu">atmos.ucla.edu</a></span></div>
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