Climate Analysis & Modeling

Climate analysis and modeling research seeks to refine our understanding of the functioning of the climate system from statistical and dynamical analysis of earth observations, and from numerical modeling of ocean-atmosphere-land-cryosphere interactions.

Physical and biophysical interactions operative in past and present climates are targeted.

Description

Climate analysis covers natural variability, anthropogenic climate change, and the effort to distinguish the two. Notable examples include the intriguing seasonal-cycles in the eastern tropical Pacific and Atlantic basins with coldest SSTs in the Northern summer/fall, and the well-known large-scale patterns of recurrent interannual variability El Nino Southern Oscillation, North Atlantic Oscillation, North Pacific Oscillation, and Pacific Decadal variability. The latter has spurred detection of the global warming fingerprints in surface temperature and hydroclimate as well as diagnosis of the structure and mechanisms of seasonal and interannual climate variability.

Climate model assessment is a recurring theme: Simulations produced by the state-of-the-art climate system models are scrutinized to assess the realism of the circulation and hydroclimate variability patterns. Representation of the atmospheric water-cycle and extreme hydrologic events (droughts and floods) in both regional and global reanalysis data sets and model simulations is a special focus.

Climate modeling activities target interactions of the physical (atmosphere, ocean, land, cryosphere) and biogeochemical (including vegetation and ocean biology) components and their interactions/feedbacks. Key feedbacks include those related to the carbon cycle. Diagnostic modeling is used to investigate the dynamical and thermodynamical interactions occurring in the troposphere and the exchanges beetween troposphere and stratosphere.

Research Areas

Global Change

Global warming detection: trends in sea-ice, snow cover, and climate variability (Farrell, Canty, Vinnikov, Salawitch, Carton, Chepurin)
Seasonal and diurnal cycles of climate trends (Vinnikov)
Estimation of global and regional land-surface temperature trends from AVHRR (Jin)
Analysis and modeling of climate sensitivity to greenhouse gas concentrations (Lau, Kirk-Davidoff)
Sampling issues in satellite climate monitoring (Kirk-Davidoff)
Coupled atmosphere-land-vegetation modeling of Sahelian climate (Lau, Zeng)
Carbon cycle and climate change: physical-biochemical interactions (Murtugudde, Salawitch, Zeng)
Bio-climate feedbacks (Murtugudde)
Earth System Modeling: Past, present, and future climates (Lau, Zeng, Murtugudde, Canty, Salawitch)
Subseasonal to seasonal climate prediction (Liang)
Mesoscale regional climate model downscaling (Liang)
Climate change projection and impact assessment (Liang)
Machine learning for climate related decision support (Liang)

Atmospheric and Oceanic Reanalyses

Historical global ocean and sea ice systems (Carton, Chepurin, Chen)
Diagnosis of 3D diabatic heating from ECMWF and NCEP Reanalyses (Nigam)

Hydroclimate Studies

Water and energy cycles and land-surface interactions (Arkin, Berbery, Jin, Lau, Nigam, Ruiz-Barradas)
Detection and prediction of urban effects on water and energy cycles
Analysis of global soil moisture variability and its remote sensing (Vinnikov, Zeng)
Surface/atmosphere radiative fluxes: Diagnosis; Land/ocean energy budgets and LDAS (Pinker, Berbery, Ruiz-Barradas)
US Drought: Initiation, maintenance, linkage with Pacific SSTs (Nigam, Ruiz-Barradas)
Asian and African Droughts (Zeng, Lau, Pinker, Yoon)
Food-energy-water nexus and sustainability (Liang)
Climate-crop interactions and agricultural productivity (Liang)

Ocean-Cryosphere-Atmosphere Interaction

Analysis and modeling of ENSO air-sea interactions (Canty, Carton, Murtugudde, Nigam, Salawitch, Zeng)
Analysis and modeling of tropical Atlantic variability (Canty, Carton, Chepurin, Grodsky, Murtugudde, Nigam, Ruiz-Barradas, Salawitch, Zeng)
Arctic climate (Carton, Chepurin, Farrell)
Diagnosis and modeling of mid-latitude air-sea interaction (Nigam)
Evolution of eastern tropical Pacific climate: ocean-atmosphere coupling and stratus clouds (Nigam, Murtugudde)
Sea ice (Farrell)

Monsoons

Dynamical modeling of Asian summer-monsoon variability, including its linkage with ENSO (Lau, Nigam, Zeng, Yoon, Murtugudde)
Mesoscale and multiscale modeling of monsoon systems (Berbery, Fox-Rabinovitz, Murtugudde)
Seasonal evolution and interannual variability of North American and South American Monsoons (Berbery, Nigam, Zeng, Yoon, Lau, Murtugudde)

Extratropical Interannual Variability

Dynamical simulation of seasonal climate anomalies (Nigam)
Structure and dynamics of stormtrack variability (Berbery, Nigam)
Analysis of North Atlantic Oscillation (NAO) structure and dynamics (Nigam)
Excitation and forcing of PNA and NPO variability (Nigam)

Clouds and Radiation

Analysis of cloud-radiation interactions (Li, Lau, Lee)
Remote sensing of clouds, forest fires, aerosols, and the radiation budget (Li)
Analysis of spectrally resolved infrared radiance from space (Kirk-Davidoff)
Multi-scale Radiation-Cloud-Convection-Circulation Interactions (Lau)

NWP methods in Climate Modeling

Hybrid coupled models for tropical climate variability (Murtugudde)

Reduced Complexity Models for Climate Forecasting

Quantification of the impacts of uncertainties in aerosol RF of climate and ocean heat uptake on projections of global warming (Canty, Salawitch)
Detection and attribution of global warming due to anthropogenic activities (Canty, Salawitch)