Scientific Program Overview (SPO): HIAPER Pole-to-Pole Observations of Atmospheric Tracers (HIPPO)

Harvard University, Cambridge MA

Investigators

Abstract

This award will enable preparation for the proposed HIAPER Pole-to-Pole Observations (HIPPO) program. HIPPO will provide the first global-scale ("pole-to-pole") survey of atmospheric tracers through the annual cycle, providing cross sections from the surface to the tropopause. It is planned to install instruments on the NSF/NCAR G-V aircraft (HIAPER) to measure a comprehensive suite of tracers, including carbon dioxide (CO2), oxygen/nitrogen ratio (O2:N2), carbon dioxide isotopomers (13CO2:12CO2), methane (CH4), carbon monoxide (CO), nitrous oxide (N2O), molecular hydrogen (H2), sulfur hexafluoride (SF6), carbonyl sulfide (COS), chlorofluorocarbons (CFCs), hydrofluorocarbons (HCFCs), and selected hydrocarbons. HIPPO will transect the mid-Pacific ocean and return over North and South America. The scientific questions motivating HIPPO focus on understanding the global carbon cycle, on defining large-scale rates of tracer transport in the troposphere and in the tropical tropopause layer, and on understanding tracer sources and sinks globally. HIPPO is intended to provide publicly available global data sets for a large suite of atmospheric tracers. It is planned to compare these data to the output of models used to assess the global distribution of sources and sinks of CO2. Additional modelers will be engaged to stimulate creative and effective application of these data.