Once upon a time a trip around the world made major headlines. Now it is a commonplace and a convenient way to measure air quality around the world by plane. A plane outfitted to measure greenhouse gases has taken off from Colorado on the first leg of a 24 day mission that will take it back and forth across the Pacific Ocean from the Arctic to the Antarctic.
The mission is part of a three year project designed to determine when and where the gases enter and leave the atmosphere. That in turn could help policymakers as well as scientists on how to handle and measure climate change.
The scientific questions that this study is focused on are (1) understanding the global sources and sinks for CO2, CH4, and other carbon cycle gases, and more broadly (2) determining large scale rates of tracer transport in the atmosphere. In other words what are the seasonal ups and downs of these gases and where do they increase (sources) and where do they decrease (sinks).
The US EPA is the source of most air quality impact assessment models used in the US for regulatory purposes, such as predicting the potential impacts from proposed stationary sources of air pollutants and mobile sources such as motor vehicles. Since motor vehicle emissions vary with regulatory changes in required emission level, it is important that impact modeling be performed with the most up-to-date models.