date: 2016-04-19T02:59:18Z pdf:PDFVersion: 1.5 pdf:docinfo:title: Evaluating the Diurnal Cycle of Upper Tropospheric Humidity in Two Different Climate Models Using Satellite Observations xmp:CreatorTool: LaTeX with hyperref package access_permission:can_print_degraded: true subject: The diurnal cycle of upper tropospheric humidity (UTH) is known to be influenced by such processes as convection and the formation of clouds which are parameterized in current global climate models. In this study, we evaluate the performance of two climate models, the Community Atmospheric Model version 5 (CAM-5) and the Global Atmosphere 3.0 (GA-3) model in simulating the diurnal cycle of UTH (represented by a combination of sinusoids of 12 and 24 h periods) by comparing with microwave and infrared (IR) measurements (where available). These comparisons were made over two convective land regions in South America and Africa, and over oceanic regions in the Atlantic, Indian and West Pacific for the month of January 2007. We analyzed how the diurnal cycles from IR and microwave instruments differ, and the reason for the differences. Our study suggests that the differences in the diurnal cycles of IR and microwave UTH result from sampling differences due to the presence of clouds. As noted by earlier studies, the models exhibit considerable discrepancies in diurnal amplitude and phase relative to observations, and these discrepancies have different magnitudes over land and ocean. dc:format: application/pdf; version=1.5 pdf:docinfo:creator_tool: LaTeX with hyperref package access_permission:fill_in_form: true pdf:encrypted: false dc:title: Evaluating the Diurnal Cycle of Upper Tropospheric Humidity in Two Different Climate Models Using Satellite Observations modified: 2016-04-19T02:59:18Z cp:subject: The diurnal cycle of upper tropospheric humidity (UTH) is known to be influenced by such processes as convection and the formation of clouds which are parameterized in current global climate models. In this study, we evaluate the performance of two climate models, the Community Atmospheric Model version 5 (CAM-5) and the Global Atmosphere 3.0 (GA-3) model in simulating the diurnal cycle of UTH (represented by a combination of sinusoids of 12 and 24 h periods) by comparing with microwave and infrared (IR) measurements (where available). These comparisons were made over two convective land regions in South America and Africa, and over oceanic regions in the Atlantic, Indian and West Pacific for the month of January 2007. We analyzed how the diurnal cycles from IR and microwave instruments differ, and the reason for the differences. Our study suggests that the differences in the diurnal cycles of IR and microwave UTH result from sampling differences due to the presence of clouds. As noted by earlier studies, the models exhibit considerable discrepancies in diurnal amplitude and phase relative to observations, and these discrepancies have different magnitudes over land and ocean. pdf:docinfo:subject: The diurnal cycle of upper tropospheric humidity (UTH) is known to be influenced by such processes as convection and the formation of clouds which are parameterized in current global climate models. In this study, we evaluate the performance of two climate models, the Community Atmospheric Model version 5 (CAM-5) and the Global Atmosphere 3.0 (GA-3) model in simulating the diurnal cycle of UTH (represented by a combination of sinusoids of 12 and 24 h periods) by comparing with microwave and infrared (IR) measurements (where available). These comparisons were made over two convective land regions in South America and Africa, and over oceanic regions in the Atlantic, Indian and West Pacific for the month of January 2007. We analyzed how the diurnal cycles from IR and microwave instruments differ, and the reason for the differences. Our study suggests that the differences in the diurnal cycles of IR and microwave UTH result from sampling differences due to the presence of clouds. As noted by earlier studies, the models exhibit considerable discrepancies in diurnal amplitude and phase relative to observations, and these discrepancies have different magnitudes over land and ocean. pdf:docinfo:creator: Ajil Kottayil, Viju O. John, Stefan A. Buehler and K. Mohanakumar PTEX.Fullbanner: This is pdfTeX, Version 3.14159265-2.6-1.40.15 (TeX Live 2014/W32TeX) kpathsea version 6.2.0 meta:author: Ajil Kottayil, Viju O. John, Stefan A. Buehler and K. Mohanakumar trapped: False meta:creation-date: 2016-04-19T02:59:18Z created: 2016-04-19T02:59:18Z access_permission:extract_for_accessibility: true Creation-Date: 2016-04-19T02:59:18Z Author: Ajil Kottayil, Viju O. John, Stefan A. Buehler and K. Mohanakumar producer: pdfTeX-1.40.15 pdf:docinfo:producer: pdfTeX-1.40.15 pdf:unmappedUnicodeCharsPerPage: 0 Keywords: upper tropospheric humidity; diurnal cycle; microwave; infrared; convection; climate models access_permission:modify_annotations: true dc:creator: Ajil Kottayil, Viju O. John, Stefan A. Buehler and K. Mohanakumar dcterms:created: 2016-04-19T02:59:18Z Last-Modified: 2016-04-19T02:59:18Z dcterms:modified: 2016-04-19T02:59:18Z title: Evaluating the Diurnal Cycle of Upper Tropospheric Humidity in Two Different Climate Models Using Satellite Observations Last-Save-Date: 2016-04-19T02:59:18Z pdf:docinfo:keywords: upper tropospheric humidity; diurnal cycle; microwave; infrared; convection; climate models pdf:docinfo:modified: 2016-04-19T02:59:18Z meta:save-date: 2016-04-19T02:59:18Z pdf:docinfo:custom:PTEX.Fullbanner: This is pdfTeX, Version 3.14159265-2.6-1.40.15 (TeX Live 2014/W32TeX) kpathsea version 6.2.0 Content-Type: application/pdf X-Parsed-By: org.apache.tika.parser.DefaultParser creator: Ajil Kottayil, Viju O. John, Stefan A. Buehler and K. Mohanakumar dc:subject: upper tropospheric humidity; diurnal cycle; microwave; infrared; convection; climate models access_permission:assemble_document: true xmpTPg:NPages: 14 pdf:charsPerPage: 2946 access_permission:extract_content: true access_permission:can_print: true pdf:docinfo:trapped: False meta:keyword: upper tropospheric humidity; diurnal cycle; microwave; infrared; convection; climate models access_permission:can_modify: true pdf:docinfo:created: 2016-04-19T02:59:18Z