This PDF file contains the front matter associated with SPIE Proceedings Volume 7089, including the Title Page, Copyright information, Table of Contents, Introduction (if any), and the Conference Committee listing.

When the first observations of a tropospheric trace gas were obtained in the 1980s, carbon monoxide enhancements from tropical biomass burning dominated the observed features. In 2005, an active remote-sensing system to provide detailed information on the vertical distribution of aerosols and clouds was launched, and again, one of the most imposing features observed was the presence of emissions from tropical biomass burning. This paper presents a brief overview of space-borne observations of the distribution of trace gases and aerosols and how tropical biomass burning, primarily in the Southern Hemisphere, has provided an initially surprising picture of the distribution of these species and how they have evolved from prevailing transport patterns in that hemisphere. We also show how interpretation of these observations has improved significantly as a result of the improved capability of trajectory modeling in recent years and how information from this capability has provided additional insight into previous measurements form satellites.

In this paper, a methodology to perform thermal and acoustic characterization of a forest fire event is reported. The analysis of fire emission properties has been carried out through laboratory and field testing, consisted in the burning of different fuels placed on tables or on field plots. The objectives of the trials have been the evaluation of fire radiated heat to fiber optic sensors with cables in open air, buried or inside the flames, and the evaluation of fire acoustic spectra, with respect to the different fuel types and fire conditions. Post processing algorithms on acquired acoustic signals have been developed to evaluate the fire frequency content, which defines the signature of the fire noise; the results obtained have confirmed the main spectrum features reported in literature. The measurement of temperature variations by fiber optic sensors has been useful to characterize sensors behavior with respect to fire, wind and smoke. The results of the tests have been used in the design phase of a new fire monitoring system made up of acoustic sensors, able to detect and track fires from the beginning, and fiber optic sensors, for a capillary monitoring of temperature in forest areas.

Scattered sunlight Multi-AXis Differential Optical Absorption Spectroscopy (MAX-DOAS) has been successfully applied to the quantitative determination of trace gas abundances in clean and polluted environments (e.g. to measure halogen oxides in polar regions, or SO₂, NO₂, CH₂O, glyoxal, and HONO in urban air) In particular volcanic plumes have been analysed for SO₂, BrO, and other species. We present and discuss promising options for the quantitative analysis of all above mentioned trace gases in biomass burning plumes, in particular in forest fire plumes. The technique allows of the total emission burden in the plume with extremely simple and compact ground - based instruments, which also can be operated automatically. Combining the measured column densities with wind speed data the total trace gas flux from the fire can be determined with good accuracy. A few examples for possible applications of the technique to monitor fire properties are given.

Basic results of a comprehensive investigation of the potential and restrictions of the remote sensing lidar technique in smoke-polluted atmospheres made in the Missoula Fire Sciences Laboratory (FSL) are presented. The study is based on the three-year lidar measurements of dynamics and optical characteristics of smoke plumes originated in prescribed burns and wildfires. For the measurements, a mobile two-wavelength scanning lidar was used. The lidar operated in the vertical scanning mode and in a combined vertical-azimuthal mode and provided detailed, range-resolved information on the smoke particulate loading up the distances and heights of 5 - 10 km from the lidar. The lidar was successfully used for the real-time determination of smoke plume dispersion, its top heights, and spatial boundaries. In some cases, the measured smoke plume tops reached heights of more than 8 km above ground level. The lidar measurements close to large wildfires also revealed numerous cases of a multilayered atmosphere with well-defined horizontally stratified smoke layers, generally, at heights between 1 and 3 km, originating in morning inversions and then sustained by the solar heating of the layers. The time series measurements allowed monitoring of their temporal transformation, including the downdraft transport of the smoke particulates to ground level. Special measurement methodology and data processing techniques for the smoke-polluted atmospheres were developed. This made it possible to obtain accurate vertical profiles of the optical characteristics of the smoke particulates, such as optical depth, and the backscatter and extinction coefficients.

The Multi-angle Imaging SpectroRadiometer (MISR) is in its ninth year of operation aboard NASA's Terra satellite. MISR acquires imagery at nine view angles between 70.5° forward and backward of nadir. Stereoscopic image matching of red band data at 275-m horizontal spatial resolution provides measurements of aerosol plume heights in the vicinity and downwind of wildfires. We are supplementing MISR's standard stereo product with more detailed, higher vertical spatial resolution stereo retrievals over individual smoke plumes, using the MISR INteractive eXplorer (MINX) analysis tool. To limit the amount of data that must be processed, MODIS (Moderate resolution Imaging Spectroradiometer) thermal anomaly data are used to identify fire locations. Data over North America are being analyzed to generate a climatology of smoke injection heights and to derive a general parameterization for the injection heights that can be used within non-plume-resolving chemical transport models. In 2002, we find that up to about 30% of fire plumes over North America reached the free troposphere. Sufficiently buoyant plumes tend to become trapped near stratified stable layers within the atmospheric vertical profile, supporting a result first obtained on a more limited set of MISR data [1]. Data from other years are being processed to further establish the robustness of these conclusions.

The Multi-angle Imaging SpectroRadiometer (MISR) instrument aboard Terra acquires imagery at 275-m resolution at nine angles ranging from 0° to 70° off-nadir. This multi-angle capability facilitates the stereoscopic retrieval of smoke heights associated with near-source plumes. A new visualization and analysis program called MISR INteractive eXplorer (MINX) takes advantage of wind-direction information inherent in smoke plumes from active fires to determine plume heights and wind speeds at higher resolution and with greater accuracy than provided by the standard, operational MISR product. Among the software tool's many features are several designed for in-depth study of plumes, including animations of the nine MISR camera images that provide a visual 3-D perspective, and interactive digitization of plumes in order to automatically retrieve heights and winds. Aerosol properties from MISR, and fire power based on infrared brightness temperatures from MODIS (also on Terra) are archived along with the retrieved height and wind data. MINX retrievals have sufficient spatial detail to provide valuable input to studies of plume dynamics as well as large-scale climatological studies. Current efforts are focusing on fires in North America, but application to other areas of the world is also envisioned. Case study examples will be presented to illustrate MINX capabilities.

Environmental satellite data provides a unique capability to monitor large areas of the globe for the occurrence of fires and the smoke that they generate which can cause considerable degradation of air quality on a regional basis. The Hazard Mapping System (HMS) incorporates seven polar and geostationary satellites into a single workstation environment. While individual satellite platforms can provide important information that can be used in air quality models, integrating several platforms allows for the combined strengths of various spacecraft instruments to overcome their individual limitations. The HMS was specifically designed as an interactive tool to identify fires and the smoke emissions they produce over North America in an operational environment. Automated fire detection algorithms are employed for each of the sensors. Analysts apply quality control procedures for the automated fire detections by eliminating those that are deemed to be false and adding hotspots that the algorithms have not detected via examination of the satellite imagery. Areas of smoke are outlined by the analyst using animated visible channel imagery. An estimate of the smoke concentration is assigned to each plume outlined. The automated Geostationary Operational Environmental Satellite (GOES) Aerosol and Smoke Product (GASP) is used as an aid in providing smoke concentrations and identifying areas of smoke. HMS analysts provide estimates on the size, initiation and duration of smoke emitting fires that are used as input to NOAA's national air quality forecast capability. This system is currently providing 48 hour smoke forecast guidance for air quality forecasters and utilizes the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model.

Biomass burning releases a significant amount of trace gases and aerosol emissions into the atmosphere. If unaccounted for in the modeling of climate, carbon cycle, and air quality, it leads to large uncertainties. The amount of biomass burning emissions depends significantly on burned areas. This study estimates near-real time burned areas from multiple satellite-based active fires in Hazard Mapping System (HMS) developed in NOAA, which capitalizes automated fire detections from Geostationary Operational Environmental Satellite (GOES) Imager, Advanced Very High Resolution Radiometer (AVHRR), Moderate Resolution Imaging Spectroradiometer (MODIS). The HMS fire counts are compared with a set of Landsat ETM+ burn scars for various ecosystems to investigate the rate of burned area in a fire count. The fire size and fire duration derived from multiple satellites are then used to calculate burned area every half hour. The estimated burned areas are evaluated using national inventory of burned area across the United States for 2005.

Various methods to generate satellite-based biomass burning emission estimates have recently been developed for their use in air quality models. Each method has different assumptions, data sources, and algorithms. This paper compares three different satellitebased biomass burning emission estimates against a control case of no biomass burning and ground-based biomass estimate in an air quality model. We have chosen August 2002 for comparison, since all data sets were readily available. In addition, there was significant wildfire activity during this month. Our results suggest that there is large uncertainty in the emission estimates which results in both under-prediction and over-prediction of PM2.5 concentration fields.

Biomass fires emit large amounts of trace gases and aerosols and these emissions are believed to significantly influence the chemical composition of the atmosphere and the earth's climate system. At the Missoula Fire Sciences Laboratory (FiSL), a MODIS direct broadcast (DB) receiving station is in place to demonstrate the potential for monitoring biomass burning in near-real-time and predicting the impact of fire emissions on air quality. A burn scar algorithm that combines active fire locations and burn scar detections for near 'real-time' measurement of fire burned areas has been developed at the Missoula FiSL. Daily wildfire burned areas in western US provide crucial input for a prototype fire emissions - smoke dispersion forecasting system.

SCIAMACHY (Scanning Imaging Absorption spectroMeter for Atmospheric ChartographY) is the first instrument to allow retrieval of CO by measuring absorption in the near infrared from reflected and scattered sunlight instead of from thermal emission. Thus, in contrast to thermal-infrared satellites (MOPITT), SCIAMACHY is highly sensitive to the lower layers of the troposphere where the sources, such as biomass burning, are located, and where the bulk of the CO is usually found. In many regions of the world, the burning of vegetation has a repeating seasonal pattern, but the amount of CO emitted from biomass burning varies considerably from place to place. Here we present a study on the relationship between fire counts and CO vertical column densities (VCD) in different regions. These results are compared with the CO VCD from MOPITT, aerosol index, and NO2 tropospheric VCD (TVCD) from SCIAMACHY, and the coupled chemistry climate model (CCM) ECHAM5/MESSY.

Satellite observations provide unique opportunities for the identification of trace gas sources on a global scale. We present case studies for the synergistic use of satellite observations by comparing formaldehyde (HCHO) time series with fire count measurements as well as with surface temperature to identify the tropospheric sources of HCHO. The fire counts and temperature are taken as proxy for biomass burning events and vegetation activity, respectively. Both are sources of HCHO, either direct or trough photochemical oxidation of non-methane hydrocarbons (e.g. biogenic isoprene emissions). Formaldehyde time series are derived from satellite observations made by the GOME instrument. This instrument provides almost 8 years of continuous HCHO global observations, which constitute an ideal case to calculate time series over specific regions for various trace gases. Nine regions have been selected to investigate the influence of fire counts (biomass burning proxy) and the temperature (vegetation activity proxy) on the HCHO tropospheric columns. The chosen time series has a length of 6 years (from July 1996 to June 2002). The results show that biogenic sources of HCHO are in many cases the strongest HCHO sources. For example over south east of the USA, the correlation with temperature was very high indicating a strong biogenic source of HCHO (through isoprene emissions). The biomass burning source typically shows more pronounced seasonal patterns or is even of sporadic nature. Over the Amazon region, the correlation with fires is high indicating that in this area most of the HCHO is caused by biomass burning. In several other regions for both sources moderate correlation coefficients were found.