Four-fold increase in solar forcing on snow in western U.S. burned forests since 1999.

Forest fires are increasing across the American West due to climate warming and fire suppression. Accelerated snow melt occurs in burned forests due to increased light transmission through the canopy and decreased snow albedo from deposition of light-absorbing impurities. Using satellite observations, we document up to an annual 9% growth in western forests burned since 1984, and 5 day earlier snow disappearance persisting for >10 years following fire.

Mapping alteration minerals at prospect, outcrop and drill core scales using imaging spectrometry.

Imaging spectrometer data (also known as 'hyperspectral imagery' or HSI) are well established for detailed mineral mapping from airborne and satellite systems. Overhead data, however, have substantial additional potential when used together with ground-based measurements. An imaging spectrometer system was used to acquire airborne measurements and to image in-place outcrops (mine walls) and boxed drill core and rock chips using modified sensor-mounting configurations.

Orbital identification of carbonate-bearing rocks on Mars.

Geochemical models for Mars predict carbonate formation during aqueous alteration. Carbonate-bearing rocks had not previously been detected on Mars' surface, but Mars Reconnaissance Orbiter mapping reveals a regional rock layer with near-infrared spectral characteristics that are consistent with the presence of magnesium carbonate in the Nili Fossae region. The carbonate is closely associated with both phyllosilicate-bearing and olivine-rich rock units and probably formed during the Noachian or early Hesperian era from the alteration of olivine by either hydrothermal fluids or near-surface water.

Spectral properties of Lake Superior banded iron formation: application to Martian hematite deposits.

Several locations have been identified on Mars that expose bulk, coarsely crystalline gray hematite. These deposits have been interpreted as being sedimentary and formed in aqueous environments. Lake Superior Type (LST) banded iron formation (BIF) was investigated as a spectral and possible process analog to these deposits.