Green 1998 obs sierra intros
The causes for major model biases (differences from observations) are studied through supplementary seasonal sensitivity experiments with various driving lateral boundary conditions (LBCs) and physics representations. precipitation annual cycle is evaluated with a 1982–2002 continuous baseline integration driven by the NCEP–DOE second Atmospheric Model Intercomparison Project (AMIP II) reanalysis. The fifth-generation PSU–NCAR Mesoscale Model (MM5)-based regional climate model (CMM5) capability in simulating the U.S. 1 for observations (OBS black) and the CMM5 simulations using the Grell (dark), and Kain–Fritsch (KF light) cumulus schemes Seasonal mean precipitation (mm day −1) averaged over the eight key regions outlined in Fig.
The vector scale is 3 m s −1 shown at top-right cornerĬMM5 precipitation (mm day −1) (a) biases (CTL − OBS) and (b) responses caused by replacing with the Kain–Fritsch cumulus scheme (KF − CTL), (c) the ERA LBC forcing (ERA − CTL), or (d) completely turning off precipitating processes over the Gulf of Mexico (GMo − CTL)įall precipitation (mm day −1) climatologies averaged over the Gulf States for observations (OBS), CMM5, and R-2 simulations during 1982–2002, as well as all AMIP models in 1979–95 and CMIP models of the last 30-yr control period The contours are ±(4, 3, 2, 1, 0.5) hPa with positive values shaded. The observations over oceans and Canada are filled by the Xie and Arkin (1996) analysis (+XA)ĬMM5 sea level pressure (hPa contours) and 850-hPa wind (m s −1 vectors) differences between the Grell (CTL) and Kain– Fritsch (KF) cumulus schemes for the 19 summers (JJA). The vector scale is 3 m s −1 shown at top-right cornerĬMM5 precipitation (mm day −1) biases (from observations) using the (a), (b) Grell (CTL) and (c), (d) Kain–Fritsch (KF) cumulus schemes as well as sensitivities (from CTL) forced by the (e), (f) ERA LBCs (ERA) and adopting (g), (h) the old cloud–radiation interaction scheme (OCR) for the (left) 1988 and (right) 1993 summers (JJA). The contours are ±(4, 3, 2, 1, 0.5) hPa with negative values shaded. 1 for observations (OBS thick solid), the CMM5 baseline integration (thick dashed), and the R-2 model output (thin dashed)ĬMM5 sea level pressure (hPa contours) and 850-hPa wind (m s −1 vectors) differences from the R-2 for winter (DJF), spring (MAM), summer (JJA), and fall (SON) averaged during 1982–2002. Monthly 1982–2002 mean precipitation (mm day −1) variations averaged over the eight key regions outlined in Fig. 3 except for the R-2 model output, where colors are replaced by contours with identical intervals (left) Observed (OBS) and (right) simulated (CMM5) precipitation (mm day −1) climatologies for winter (DJF), spring (MAM), summer (JJA), and fall (SON) averaged during 1982–2002 The hatched edge areas are the buffer zones, where LBCs are specifiedĪnnual mean differences between the SWM and STM rainfall analyses during 1982–99, depicting precipitation enhancement by the PRISM Outlined are eight key regions and four major sectors separated by the cross dot–dashed lines.