Objective

1
Assessment of the Impact of Different Land
Surface Models and Land Initial Conditions on the
Monsoon Climate in the NCEP Climate Forecast
System Evaluations over Asian Monsoon Region and
Indo-Pacific Sector 1Soo-Hyun Yoo , 1Jae Schemm,
1Song Yang, 2Rongqian Yang, and 2Kenneth
Mitchell 1Climate Prediction Center
2Environmental Modeling Center, NCEP/NWS/NOAA,
Camp Springs, Maryland 20746, USA
Objective To understand the impact of new land
surface model (LSM) and land initial condition
(IC) on Asian monsoon climate and its
relationship with Indo-Pacific SST in the NCEP
Climate Forecasting System (CFS).

• Data
• SST Reynolds/NCEP version 2 monthly 1x1
  optimally interpolated SST (OISST)
• Winds NCEP/NCAR reanalysis data (144x73)
• Precipitation monthly CPC Merged Analysis of
  Precipitation (CMAP) data (144x72)
• 2m Temperature GHCN/CAMs Global T2m (T126)
• Model Experiments
• Models NCEP CFST126L64 (GFS-OP3T3 MOM-3) with
  OSU LSM (2 soil layers)/Noah LSM (4 soil layers)
• Initial conditions Apr 19-23, 29, 30, and May
  1-3 from Global Reanalysis 2 (GR2)/Global Land
  Data Assimilation System (GLDAS)
• Four configurations of T126 CFS hindcast runs
• a) OSU_GR2 OSU LSM with initial land states
  from GR2
• b) Noah_GR2 Noah LSM with initial land
  states from GR2
• c) Noah_GLDAS Noah LSM with initial land
  states from T126 GLDAS/Noah
• d) Noah_GLDAS_Clim Noah LSM with initial
  land states from GLDAS/Noah Climatology
• Experiments 6-month (up to September) forecast
  runs from 1980 to 2004
• Main Issues
• Improvement from OSU to Noah LSM Comparison
  between the configuration a) and b)
• Importance of land Ics Comparison among the
  configuration b), c), and d)

• Summary
• CFS simulations change more noticeably between
  different land models than among different land
  initial conditions.
• The summer climatologies over Asia are more
  reasonably simulated in CFS Noah LSM compatible
  GLDAS initial conditions than other model
  configurations.
• Correlation scores for precipitaion and 2-meter
  temperature are the best over subtropical Asia
  in configuration CFS Noah_GLDAS.