The ITCT 2K2 study is primarily an exploratory mission. These specific science questions are meant to give a general framework for mission planning. Answering them should be possible in the context of one intensive field program, and will be a first step toward answering the more general science questions discussed in the overall ITCT White Paper .
- Is it possible to discover relationships between in situ measurements that allow the contribution to the composition associated with emission from each source to be identified and quantified? Will measurements of trace chemicals or aerosol chemical composition provide elemental and/or chemical speciation fingerprints for different source classes or source regions?
- What mechanisms control the export of emissions from Asia, Mexico-Central America, and North America to the North Pacific Ocean? Preliminary analysis of TRACE-P results indicate that biomass burning emissions are primarily lofted by convection over south Asia, while anthropogenic emissions from east Asia are transported both aloft due to frontal passage and within boundary layer outflow following frontal passage.
- What processes are inherent in these export mechanisms that significantly affect the ultimate fates of emissions exported from the various continental regions? Convection and some of the frontal lofting outflow likely involves more scrubbing of soluble species than boundary layer outflow, while the latter may be more influenced by dry deposition.
- How does the composition of the anthropogenic emissions change during transport, and what is the effect upon ozone, aerosols and other photochemical products? How do ratios of aerosol composition, e.g. sulfate to nitrate or organic carbon to Ca, compare to those observed in the outflow regions during TRACE-P, ACE-Asia and PEACE-B? Do measures of photochemical aging – propane/ethane, acetylene/CO – provide useful indicators to follow evolution of primary emissions and/or aerosol parameters?
- What are the magnitude and ultimate impact of emissions from commercial shipping and air transport in the Pacific? Can we carry out ship plume evolution studies to quantitatively determine the rates of transformation and removal of the emitted species? How do these rates compare with plume dispersal rates in the marine boundary layer?
- Can we find evidence of influence from continental sources upwind of Asia (Europe, Tropical regions, or globally circulated North American emissions)? Do measures of photochemical aging – propane/ethane, acetylene/CO – provide useful indicators of source continent?