Treesearch

Fuel consumption specifies the amount of vegetative biomass consumed during wildland fire. It is a two-stage process of pyrolysis and combustion that occurs simultaneously and at different rates depending on the characteristics and condition of the fuel, weather, topography, and in the case of prescribed fire, ignition rate and pattern. Fuel consumption is the basic process that leads to heat absorbing emissions called greenhouse gas and other aerosol emissions that can impact atmospheric and ecosystem processes, carbon stocks, and land surface reflectance. It is a critical requirement for...

Wildland fires have influenced the global carbon cycle for 420 million years of Earth history, interacting with climate to define vegetation characteristics and distributions, trigger abrupt ecosystem shifts, and move carbon among terrestrial and atmospheric pools. Carbon dioxide (CO2) is the dominant driver of ongoing climate change and the principal emissions component of wildland fires, while black carbon and other aerosols found in fire emissions contribute to uncertainties in climate projections. Fire emissions research to date has been focused on developing knowledge for air pollution...

While the vast majority of carbon emitted by wildland fires is released as CO2, CO, and CH4, wildland fire smoke is nonetheless a rich and complex mixture of gases and aerosols. Primary emissions include significant amounts of CH4 and aerosol (organic aerosol and black carbon), which are short-lived climate forcers. In addition to CO2 and short-lived climate forcers, wildland fires release CO, non-methane organic compounds (NMOC), nitrogen oxides (NOx = NO +NO2), NH3, and SO2. These species play a role in radiative forcing through their photochemical processing, which impacts atmospheric...

Current remote sensing studies of phenology have been limited to coarse spatial or temporal resolution and often lack a direct link to field measurements. To address this gap, we compared remote sensing methodologies using Landsat Thematic Mapper (TM) imagery to extensive field measurements in a mixed northern hardwood forest. Five vegetation indices, five mathematical fits to model a continuous temporal response, and a suite of threshold estimates for "start of spring/season" (SOS) assessments were compared to field measurements of bud burst stage and hemispherical photo derived canopy...

A set of climate change projections for the United States was developed for use in the 2010 USDA Forest Service RPA Assessment. These climate projections, along with projections for population dynamics, economic growth, and land use change in the United States, comprise the RPA scenarios and are used in the RPA Assessment to project future renewable resource conditions 50 years into the future. This report describes the development of the historical and projected climate data set. The climate variables are monthly total precipitation in millimeters (mm), monthly mean daily maximum air...

Biomass burning is a major source of greenhouse gases, aerosols, black carbon, and atmospheric pollutants that affects regional and global climate and air quality. The spatial and temporal extent of fires and the size of burned areas are critical parameters in the estimation of fire emissions. Tremendous efforts have been made in the past 12 years to characterize the variability of fire locations and burned areas using high frequency satellite observations (e.g., MODIS, GOES) and improved ground-based reports. We describe and compare the major global and regional (e.g., western United...

Sixty percent of the Southern United States landscape is forested (Wear 2002). Forest types vary greatly among the five subregions of the South, which include the Coastal Plain, Piedmont, Appalachian-Cumberland, Mid-South, and the Mississippi Alluvial Valley. Current inventory data show upland hardwood forests being the predominant forest type in the South (>30 million ha) followed by planted pine (>15 million ha), natural pine and bottomland hardwoods (~13 million ha), and oak-pine (>3 million ha) forest types (Huggett et al. in press). These forest ecosystems provide a multitude of...

The climate of the 13 Southern United States is generally thought to be changing in response to global and continental scale influences; and by 2060, average annual temperature is predicted to be higher and precipitation lower than for the year 2000, the date defined as current for the purposes of this analysis (Figure 10.1). Some southern forest species and communities may be highly vulnerable to the effects of changing climate, possibly resulting in conversion of woodland to savanna or grassland (Bosworth et al. 2008). In addition to the effects of temperature and precipitation on...

In the southeastern United States, climate models project a temperature increase of 2-10°C by 2100 (Intergovernmental Panel on Climate Change 2007). Climate change is already evident. Since the 1970s, average temperature has risen by about 1°C, with the greatest seasonal temperature increase during winter. Average precipitation during autumn has increased by 30% since 1901, but summer precipitation has decreased (U.S. Global Change Research Program 2012). Correspondingly, drought has affected a larger portion of the Southeast over the past three decades. The patterns and severity of storms...

Thinking of the Northern Forest brings to mind spruce/fir (S/F) forests, cool climates, and high elevations: not to mention fishing and canoe trips: however, spruce and fir are also very important to the northern timber economy and rural development. Considering new concerns over the spruce budworm, an update on the status of this critically important forest resource is timely.