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Valero, FPJ, Collins WD, Pilewskie P, Bucholtz A, Flatau PJ.  1997.  Direct radiometric observations of the water vapor greenhouse effect over the equatorial Pacific ocean. Science. 275:1773-1776.   10.1126/science.275.5307.1773   AbstractWebsite

Airborne radiometric measurements were used to determine tropospheric profiles of the clear sky greenhouse effect. At sea surface temperatures (SSTs) larger than 300 kelvin, the clear sky water vapor greenhouse effect was found to increase with SST at a rate of 13 to 15 watts per square meter per kelvin. Satellite measurements of infrared radiances and SSTs indicate that almost 52 percent of the tropical oceans between 20 degrees N and 20 degrees S are affected during all seasons. Current general circulation models suggest that the increase in the clear sky water vapor greenhouse effect with SST may have climatic effects an a planetary scale.

Valero, FPJ, Bucholtz A, Bush BC, Pope SK, Collins WD, Flatau P, Strawa A, Gore WJY.  1997.  Atmospheric Radiation Measurements Enhanced Shortwave Experiment (ARESE): Experimental and data details. Journal of Geophysical Research-Atmospheres. 102:29929-29937.   10.1029/97jd02434   AbstractWebsite

Atmospheric Radiation Measurements Enhanced Shortwave Experiment (ARESE) was conducted to study the magnitude and spectral characteristics of the absorption Of solar radiation by the clear and cloudy atmosphere. Three aircraft platforms, a Grob Egrett, a NASA ER-2, and a Twin Otter, were used during ARESE in conjunction with the Atmospheric Radiation Measurements (ARM) central and extended facilities in north central Oklahoma. The aircraft were coordinated to simultaneously measure solar irradiances in the total spectral broadband (0.224-3.91 mu m), near infrared broadband (0.678-3.3 mu m), and in seven narrow band-pass (similar to 10 nm width) channels centered at 0.500, 0.862, 1.064, 1.249, 1.501, 1.651, and 1.750 mu m. Instrumental calibration issues are discussed in some detail, in particular radiometric power, angular, and spectral responses. The data discussed in this paper are available at the ARM ARESE data archive via anonymous FTP to ftp.arm.gov.

Verlinde, J, Flatau PJ, Cotton WR.  1990.  Analytical Solutions to the Collection Growth Equation - Comparison with Approximate Methods and Application to Cloud Microphysics Parameterization Schemes. Journal of the Atmospheric Sciences. 47:2871-2880.   10.1175/1520-0469(1990)047<2871:asttcg>2.0.co;2   AbstractWebsite

A closed form solution for the collection growth equation as used in bulk microphysical parameterizations is derived. Although the general form is mathematically complex, it can serve as a benchmark for testing a variety of approximations. Two special cases that can immediately be implemented in existing cloud models are also presented. This solution is used to evaluate two commonly used approximations. The effect of the selection of different basis functions is also investigated.

Vogelmann, AM, Flatau PJ, Szczodrak M, Markowicz KM, Minnett PJ.  2003.  Observations of large aerosol infrared forcing at the surface. Geophysical Research Letters. 30   10.1029/2002gl016829   AbstractWebsite

Studies of aerosol effects on the Earth's energy budget usually consider only the cooling effects at short (solar) wavelengths, but we demonstrate that they also have important warming effects at thermal infrared (IR) wavelengths that have rarely been observed and are commonly ignored in climate models. We use high-resolution spectra to obtain the IR radiative forcing at the surface for aerosols encountered in the outflow from northeastern Asia. The spectra were measured by the Marine-Atmospheric Emitted Radiance Interferometer (M-AERI) from the NOAA Ship Ronald H. Brown during the Aerosol Characterization Experiment-Asia (ACE-Asia). We show that the daytime surface IR forcing are often a few Wm(-2) and can reach almost 10 Wm(-2) for large aerosol loadings. Thus, even the smaller aerosol IR forcing observed here are comparable to or greater than the 1 to 2 Wm(-2) IR surface enhancement from increases in greenhouse gases. These results highlight the importance of aerosol IR forcing which should be included in climate model simulations.