Title: Near‐Cloud Aerosol Retrieval Using Machine Learning Techniques, and Implied Direct Radiative Effects

Journal Article · · Geophysical Research Letters
ORCiD logo [1]; ORCiD logo [1]; ORCiD logo [2]; ORCiD logo [3]; ORCiD logo [4]; ORCiD logo [5]; ORCiD logo [6]; ORCiD logo [7]
  1. Department of Atmospheric Science Colorado State University Fort Collins CO USA
  2. NASA Goddard Space Flight Center Greenbelt MD USA
  3. NOAA Chemical Sciences Laboratory Boulder CO USA
  4. NASA Goddard Space Flight Center Greenbelt MD USA, Joint Center for Earth System Technology University of Maryland Baltimore County Baltimore MD USA
  5. NASA Goddard Space Flight Center Greenbelt MD USA, GESTAR/Morgan State University Baltimore MD USA
  6. NOAA Chemical Sciences Laboratory Boulder CO USA, Cooperative Institute for Research in Environmental Sciences University of Colorado Boulder CO USA
  7. Department of Atmospheric Science Colorado State University Fort Collins CO USA, Department of Meteorology University of Reading Reading UK

Abstract There is a lack of satellite‐based aerosol retrievals in the vicinity of low‐topped clouds, mainly because reflectance from aerosols is overwhelmed by three‐dimensional cloud radiative effects. To account for cloud radiative effects on reflectance observations, we develop a Convolutional Neural Network and retrieve aerosol optical depth (AOD) with 100–500 m horizontal resolution for all cloud‐free regions regardless of their distances to clouds. The retrieval uncertainty is 0.01 + 5%AOD, and the mean bias is approximately −2%. In an application to satellite observations, aerosol hygroscopic growth due to humidification near clouds enhances AOD by 100% in regions within 1 km of cloud edges. The humidification effect leads to an overall 55% increase in the clear‐sky aerosol direct radiative effect. Although this increase is based on a case study, it highlights the importance of aerosol retrievals in near‐cloud regions, and the need to incorporate the humidification effect in radiative forcing estimates.

Research Organization:
National Oceanic and Atmospheric Administration (NOAA), Boulder, CO (United States). NOAA Chemical Sciences Laboratory (CSL); Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). Atmospheric Radiation Measurement (ARM) Data Center
Sponsoring Organization:
Cooperative Institute for Research in the Atmosphere; European Research Council (ERC); National Aeronautics and Space Administration (NASA); National Science Foundation (NSF); USDOE; USDOE Office of Science (SC), Biological and Environmental Research (BER)
Contributing Organization:
Argonne National Laboratory (ANL); Brookhaven National Laboratory (BNL); Oak Ridge National Laboratory (ORNL); Pacific Northwest National Laboratory (PNNL)
Grant/Contract Number:
89243020SSC000055; AC05-76RL01830
OSTI ID:
1893549
Journal Information:
Geophysical Research Letters, Journal Name: Geophysical Research Letters Journal Issue: 20 Vol. 49; ISSN 0094-8276
Publisher:
American Geophysical Union (AGU)Copyright Statement
Country of Publication:
United States
Language:
English

References (37)

Near-cloud aerosol properties from the 1 km resolution MODIS ocean product: Near-cloud aerosols in MODIS ocean data journal February 2014
Multiangle photopolarimetric aerosol retrievals in the vicinity of clouds: Synthetic study based on a large eddy simulation journal November 2016
Testing the two-layer model for correcting near-cloud reflectance enhancement using LES/SHDOM-simulated radiances journal August 2016
Improvement of MODIS aerosol retrievals near clouds journal August 2013
Early Stopping - But When? book January 1998
Visualizing and Understanding Convolutional Networks book January 2014
Simultaneous measurement of light-scattering properties and particle size distribution for aerosols: Application to ammonium sulfate and quartz aerosol particles journal July 2007
Extending 3D near-cloud corrections from shorter to longer wavelengths journal November 2014
Explaining nonlinear classification decisions with deep Taylor decomposition journal May 2017
Neural network attribution methods for problems in geoscience: A novel synthetic benchmark dataset journal January 2022
Deep convection as a source of new particles in the midlatitude upper troposphere: DEEP CONVECTION AS A SOURCE OF NEW PARTICLES journal November 2002
A simple model for the cloud adjacency effect and the apparent bluing of aerosols near clouds journal January 2008
On the twilight zone between clouds and aerosols: CLOUDS TWILIGHT ZONE journal April 2007
MODIS observations of enhanced clear sky reflectance near clouds journal January 2009
Effect of changes in relative humidity on aerosol scattering near clouds journal January 2009
Effect of aerosol on trade cumulus cloud morphology journal January 2009
Exploring Aerosols Near Clouds With High‐Spatial‐Resolution Aircraft Remote Sensing During SEAC 4 RS journal February 2019
Aerosol‐Cloud Interactions in Trade Wind Cumulus Clouds and the Role of Vertical Wind Shear journal November 2019
Bounding global aerosol radiative forcing of climate change journal November 2019
Effect of nonprecipitating clouds on the aerosol size distribution in the marine boundary layer journal February 1986
Impact of 3-D Clouds on Clear-Sky Reflectance and Aerosol Retrieval in a Biomass Burning Region of Brazil journal January 2006
The Spherical Harmonics Discrete Ordinate Method for Three-Dimensional Atmospheric Radiative Transfer journal February 1998
The Accuracy of Determining Three-Dimensional Radiative Transfer Effects in Cumulus Clouds Using Ground-Based Profiling Instruments journal July 2005
Rain in Shallow Cumulus Over the Ocean: The RICO Campaign journal December 2007
Incorporating the Effects of 3D Radiative Transfer in the Presence of Clouds into Two-Stream Multilayer Radiation Schemes journal February 2013
The MODIS Aerosol Algorithm, Products, and Validation journal April 2005
On Pixel-Wise Explanations for Non-Linear Classifier Decisions by Layer-Wise Relevance Propagation journal July 2015
Dataset associated with "Near-Cloud Aerosol Retrieval Using Machine Learning Techniques, and Implied Direct Radiative Effects" dataset January 2022
The Dark Target Algorithm for Observing the Global Aerosol System: Past, Present, and Future journal September 2020
Mapping the Twilight Zone—What We Are Missing between Clouds and Aerosols journal June 2017
On the climate forcing consequences of the albedo continuum between cloudy and clear air journal September 2007
Investigating the influence of noise and distractors on the interpretation of neural networks preprint January 2016
Deep Learning using Rectified Linear Units (ReLU) preprint January 2018
Feasibility study of multi-pixel retrieval of optical thickness and droplet effective radius of inhomogeneous clouds using deep learning journal January 2017
Analysis of co-located MODIS and CALIPSO observations near clouds journal January 2012
MODIS 3 km aerosol product: algorithm and global perspective journal January 2013
The Collection 6 MODIS aerosol products over land and ocean journal January 2013