Comparison of modelled atmospheric aerosol content and its influence on high-energy laser propagation

Aerosol content of the atmosphere is an important factor in the propagation of high-energy laser (HEL) beams. Aerosol absorption leads to the thermal blooming effect, where the laser beam heats the air and thereby creates a diverging lens. We have used three methods to estimate the aerosol absorption coefficient: (1) a Mie calculation on...

Taking a snapshot of atmospheric aerosols and their optical properties

The Advanced Navy Aerosol Model provides a quick and simple method to estimate aerosol properties in the maritime atmosphere using standard meteorological parameters

The Advanced Navy Aerosol Model (ANAM): Validation of small-particle modes

The image quality of electro-optical sensors in the (lower-altitude marine) atmosphere is limited by aerosols, which cause contrast reduction due to transmission losses and impact on the thermal signature of objects by scattering solar radiation. The Advanced Navy Aerosol Model (ANAM) aims at providing a quantitative estimate of the aerosol...

Satellite retrieved aerosol properties for battlespace characterization and sensor performance

Sea basing operations in coastal environments require a rapid and accurate description of the physical conditions in the region. Battlespace characterization and sensor performance assist in optimizing the efficiency and safety of operations, of which the detection of targets at low level above the sea surface is all-important. The environmental...

Comparison of aerosol size distribution in coastal and oceanic environments

The results of applying the empirical orthogonal functions (EOF) method to decomposition and approximation of aerosol size distributions are presented. A comparison was made for two aerosol data sets, representing coastal and oceanic environments. The first data set includes measurements collected at the Irish Atlantic coast in 1994 and 1995,...

Improvements in the Advanced Navy Aerosol Model (ANAM)

The Navy Aerosol Model (NAM) is widely used as an engineering tool to provide a quick estimate of the aerosol extinction in the marine environment. Since its introduction, several shortcomings of NAM have been identified that are being addressed by the development of the Advanced Navy Aerosol Model (ANAM). At present, the Advanced Navy Aerosol...

Combining ANAM with satellite data to determine the EOSTAR aerosol component

The detection of targets at low levels above the sea surface by electro-optical (EO) sensors is affected by the atmosphere. Models have been developed to describe the electro-optical propagation in the marine atmospheric surface layer as a function of meteorological parameters. EOSTAR is an end-to-end model suite for EO sensor performance in...

ANAM vs. NAM: Is the difference significant?

The Navy Aerosol Model (NAM, available in MODTRAN) is widely used as a tool to assess the aerosol extinction in the marine atmospheric surface layer. NAM was built as a regression model in the 1980s to represent the aerosol extinction at deck height as a function of the meteorological conditions. The recently developed Advanced Navy Aerosol...

Near-surface aerosol transmission in the marine environment

An extensive data set of aerosol vertical concentration profiles (height range 0.5-15 meters, diameter range 10-75 micron), acquired with the Rotorod3 device at various geographical locations has been statistically analyzed. The analysis supplied a parameterization for the 4th (large particle) lognormal mode in the Advanced Navy Aerosol Model ...

Characterizing large aerosols in the lowest level of the marine atmosphere

This paper discusses techniques to describe the aerosol and the electro optical properties of the marine atmosphere from 15 meters down to the tops of the highest wave. Emphasis is placed on the experimental Rotorod technique to measure the concentrations of giant sea salt droplets. Data from these devices are parameterized using a lognormal...