A -- Trace Gas Measurements at Barbados

In the absence of other qualified sources, it is the intent of the National Oceanic and Atmospheric Administration (NOAA) of the Department of Commerce to award a sole source contract to International Science Consultants, 39 Avon Castle Drive, Ringwood, Hants, United Kingdom BH24 2BB, for a study to measure trace gas concentrations in Barbados. Background: The Barbados site is one of four comprising the Global Atmospheric Gases Experiment (GAGE) network. This network was established to monitor the long-term trends of several the trace gas species (listed below) that cause stratospheric ozone destruction. Data from the network are analyzed for long-term trends, changes in sources, and global budgets and published jointly by the GAGE research team. The species are key compounds in the issues of stratospheric ozone depletion and "greenhouse" climate warming. Thus, there is a fundamental scientific need to monitor the atmospheric concentrations of these species, and document their long-term increase. To establish the long-term change with high precision, the measurements must be made with a frequency of at least several observations per day. NOAA proposes to establish a contract with International Science Consultants (ISC) to continue the Barbados record for a period of one year with options to renew the contract up to four additional years. There is a critical scientific requirement that the future measurements are directly linked to those of the past and to the other sites of the GAGE network without any breaks in the data. This linkage is important as all of the gases measured are changing in concentration over the space of weeks and their growth rates are also changing. Without a continuous record that is accurate, the sources and sinks of the gases of interest cannot be defined. The continuous measurement of ozone deleting gases in the atmosphere is mandated by Congress and must be reported each year for the prior year. This requirement is completely inflexible and, without this link to the past, the future measurements would have minimal value. Current Requirement: The proposed contract is to obtain ambient air concentrations continuously, every 40 minutes, of CFCl3, CF2Cl2, CCl4, CH3CCl3, N20, CH4, CHCl3, and CF2ClCFCl2 taken within 100 meters of the seacoast at East Point (also known as Ragged Point), Barbados. The measurements should be made for 5 years beginning approximately June 21, 2003. Measurements shall be made with an accuracy (relative to previous ALE-GAGE measurements) of 0.5% for CH4 and 1% for all other species. The measurements shall be directly comparable to previous measurements made at the same location since 1978 by the Atmospheric Lifetime Experiment and GAGE. Instruments for making the measurements shall be housed in an air-conditioned shelter. Results of the measurements shall be provided to NOAA as daily mean concentrations and associated standard deviation of each species within four months of the measurement. To be considered, respondents must submit evidence substantiating that each of the following qualification requirements can be met: (1) Demonstrated experience using gas chromatographs for high-precision atmospheric measurements of the species required. (2) Demonstrated access to gas calibration standards of all species used for the ALE and GAGE experiments. (3) Demonstrated ability to install gas chromatographic instruments for unattended operation for high-precision trace gas measurements at a remote location. (4) Demonstrated capability to install and operate the instruments at Ragged Point, Barbados. (5) Demonstrated capability to provide continuity with, and direct comparability to, the similar measurements made at the location since 1978. This is not a formal solicitation. See notes 22 and 26.