Insights into Shallow Cumulus Surface Radiative Effect Utilizing Observations, High Resolution Modeling, and 3-D Radiative Transfer Simulations
Abstract
Solar radiation absorbed at the surface is the primary driver of the Earth-atmosphere system. Cloud cover strongly modulates surface solar radiation, but correctly understanding and modeling the magnitude and distribution of radiation under broken cloud can be both intellectually and computationally challenging. This is particularly true for shallow cumulus clouds, which are common across continents and oceans alike, but are small in spatial scale and evolve quickly. Using new routine Large Eddy Simulation (LES) along with observations at the Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) atmospheric observatory, multiple shallow cumulus cases and their corresponding surface radiative effects are investigated. This presentation will reveal the stark differences between observed and modeled probability distributions of down-welling surface solar irradiance when neglecting 3-D radiative effects. It will be demonstrated that the shape of the observed distribution can only be reproduced when the LES output is ingested into a 3-D Monte Carlo radiative transfer simulator. Differences between calculations with and without 3-D radiative effects are then used to determine whether systematic biases remain at increasing spatial and temporal scales. The improved understanding that is emerging from this work is providing valuable insight for evaluating state-of-the-art weather prediction models, and will have important implications for assessing solar renewable energy potential in the future.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.A23T2983G
- Keywords:
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- 3311 Clouds and aerosols;
- ATMOSPHERIC PROCESSES;
- 3359 Radiative processes;
- ATMOSPHERIC PROCESSES;
- 3360 Remote sensing;
- ATMOSPHERIC PROCESSES