Ice crystal larger than about 5 μm diameter were separated from interstitial particles in aircraft contrails and evaporated. Residual particles larger than 0.1 μm were analyzed by electron microscopy. Soot, metals, and volatile organic substances, apparently from the aircraft exhaust, were found. However, the residual particles also contained high percentages...
Measurements of ice water content (IWC) and
mean ice-crystal size and concentration made by two in-situ
probes, C, VI and PVM, were compared on the DC-8 aircraft
during SUCCESS flights in orographic ice clouds. The
comparison of 1WC in these wave clouds, that formed at
temperatures of about -38 °C...
In situ measurements of water vapor and temperature from recent aircraft campaigns have provided evidence that the upper troposphere is frequently supersaturated with respect to ice. The peak relative humidities with respect to ice (RHI) occasionally approached water saturation at temperatures ranging from -40°C to -70°C in each of the...
In flight through a wave cloud during SUCCESS on 2 May 1996, simultaneous forward- and aft- facing NOy inlets were used to infer the amount of condensed-phase NOy present on ice particles that were up to a few minutes old. Condensed-phased amounts were 25-75 pptv, or 10-20% of gas-phase NOy....
The ambient temperatures and humidities required for contrail formation
and persistence are determined from in situ measurements during the
Subsonic Aircraft: Contrail and Cloud Effects Special Study (SUCCESS) experiment.
Ambient temperatures and water vapor concentrations were measured
with the meteorological measurement system, a laser hygrometer, and a cryogenic
hygrometer (all...
A case study of new particle formation in the region downwind of a mesoscale convective system stretching across much of the central United States is presented. Airborne measurements were made of condensation nuclei (CN), cloud particle surface area, water vapor, and other gases. CN concentrations were greatly enhanced above and...
We report the first measurements of CO₂, CH₄,
N₂O, CO₂, and H₂O(g) in the exhaust trails of T-39, B-757, and
DC-8 aircraft at cruise conditions. Emission indices (El)
derived from these in-situ measurements are presented.
Results are in agreement with ground-based tests indicating
aircraft act as a net sink for...
We have compared in situ measurements
near the leading-edges of wave-clouds observed during
the SUCCESS experiment with numerical simulations.
Observations of high supersaturations with respect to ice (> 50%) near the leading edge of a very cold wave cloud (T < -60°C) are approximately consistent
with recent theoretical and laboratory...
The Blanco Trough, a deep depression located in the Blanco Fracture Zone near the intersection with the Juan de Fuca Ridge, contains unusual manganese-enriched layered sediments. Due to the Blanco Trough's bathymetric isolation and confinement, and its location in a tectonically active zone, three hypotheses concerning the origin and cause...