National Aeronautics and Space Administration

Living With A Star

Targeted Research and Technology


ROSES ID: NNH05ZDA001N      Selection Year: 2006      

Program Element: Independent Investigation

Principal Investigator: Robert Cahalan

Affiliation(s): NASA/Goddard Space Flight Center

Project Member(s):
Pilewskie, Peter Co-I University of Colorado
Wen, Guoyong Co-I NASA/Goddard Space Flight Center


The Sun's radiative input to Earth has characteristic temporal variations that depend on wavelength, as we have documented under previous funding. We propose to further analyze SIM (Spectral Irradiance Monitor) solar spectral irradiance (SSI) data, and compare with SSI synthesized from the SRPM model (Solar Radiation Physical Modeling), to estimate the statistical relations between SSI and total solar irradiance (TSI), to study the responses of atmosphere-ocean mixed layer to variations in solar spectral irradiance. Proposed research will include the analysis of existing solar spectral irradiances from SORCE SIM, with coincident ground-based and aircraft observations from the Solar Spectral Flux Radiometer (SSFR) to estimate spectral solar forcing in the troposphere and stratosphere, and to model the atmospheric response to variations in SSI, to advance our understanding of the wavelength and time dependence of solar forcing of Earth's atmosphere-ocean system. This proposal falls into the category of Independent Investigations, and has three tasks:

(1) Variations in Spectral Solar Irradiance (SSI): Extend the analysis of SSI from SIM on SORCE to the fully calibrated time series and compare with synthesized solar spectrum from the SRPM model (Solar Radiation Physics Modeling). Estimate the statistical relations between of SSI and TSI.

(2) Spectral Solar Forcing: Estimate the vertical profiles of spectral and total solar forcing by analyzing the existing SORCE SSI, with coincident ground-based and aircraft observations from the Solar Spectral Flux Radiometer (SSFR).

(3) Modeling the response of the atmospheric and surface temperature to the variations of SSI: A simple radiative-convective model (RCM) will be used to study atmospheric and surface responses to variations in SSI. The 1-D RCM will be extended to account for time-dependence of both variation of SSI and response of atmosphere-ocean mixed layer.


Performance YearReferenceInvestigation TypeActions
1Oreopoulos, Lazaros; Marshak, Alexander; Cahalan, Rober...
not set
1Sud, Y. C.; Walker, G. K.; Zhou, Y. P.; Schmidt, G...
not set
1Sud, Y. C.; Walker, G. K.; Zhou, Y. P.; Schmidt, G...
not set
1Cahalan, Robert F.; Wen, Guoyong; Harder, Jerald W.;...
not set


Performance YearReferenceActions
1Cahalan, Robert; Wen, Guoyong; Pilewskie, Peter; Harde...

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