Airborne observations of greenhouse gases in the North Slope of Alaska during summer 2015

Abstract:

Atmospheric temperatures are warming faster in the Arctic than predicted by climate models. The impact of this warming on permafrost degradation is not well understood, but it is projected to increase carbon decomposition and greenhouse gas production (CO₂ and/or CH₄) by arctic ecosystems. Airborne observations of atmospheric trace gases, aerosols and cloud properties in North Slopes of Alaska (NSA) are improving our understanding of global climate, with the goal of reducing the uncertainty in global and regional climate simulations and projections.

From June 1 through September 15, 2015, the Atmospheric radiation measurement (ARM) airborne facility (AAF) deployed a G1 research aircraft (ARM-ACME-V mission) to fly over the North Slope of Alaska, with occasional vertical profiling to measure trace gas concentrations, between Prudhoe Bay, Oliktok point, Barrow, Atqasuk, Ivotuk, and Toolik Lake. The aircraft payload includes a Picarro and a LGR analyzers for continuous measurements of CO₂, CH₄, H₂O, and CO and N₂O mixing ratios, and a 12-flask sampler for analysis of carbon cycle gases (CO₂, CO, CH₄, N₂O, ¹³CO₂, ¹⁴CO₂, carbonyl sulfide, and trace hydrocarbon species including ethane). The aircraft payload also include measurements of aerosol properties (number size distribution, total number concentration, absorption, and scattering), cloud properties (droplet and ice size information), atmospheric thermodynamic state, and solar/infrared radiation. Preliminary results using CO₂, CH₄, CO, ethane, and soot spectroscopy observations are used to tease apart biogenic and thermogenic (biomass burning, and oil and gas production) contributions