Earth System Research Laboratory Ozone Water Vapor Group Water Vapor Flight Measurements

The Ozone and Water Vapor Group is part of NOAA's Earth System Research Laboratory (ESRL) in Boulder, CO. The Ozone Water Vapor Group conducts research on the nature and causes of the depletion of the stratospheric ozone layer and the role of stratospheric and tropospheric ozone and water vapor in forcing climate change and in modifying the chemical cleaning capacity of the atmosphere. This is accomplished through long-term observations and intensive field programs that measure ozone and water vapor levels in the upper troposphere and stratosphere. The Reference Network used by the Ozone and Water Vapor Group is part of NOAA's Earth System Research Laboratory in Boulder, CO. The measurement programs include Total Column Ozone Measurements (Dobson Ozone), Surface Ozone Measurements, Ozonesonde Measurements using balloons, and Water Vapor measurements using balloons.

Since 1980, the Ozone and Water Vapor group has made in situ measurements of atmospheric water vapor mixing ratios (mole fractions) from the lower free troposphere (~2 km) up to the middle stratosphere (~28 km). These measurements are made using a balloon-borne payload including a NOAA frost point hygrometer, an electrochemical concentration cell, ozonesonde, and a radiosonde to measure temperature, pressure, and payload location via GPS. The payloads are built and calibrated in the laboratory in Boulder, CO. These hygrometers are flown monthly from Boulder to Hilo, Hawaii and Lauder, New Zealand. The primary research focus is the long-term monitoring of upper tropospheric and lower stratospheric water vapor and the processes that control its abundance in the atmosphere. Water vapor is a natural and important component of the Earth's atmosphere. The distribution of water vapor influences physical and chemical properties of the atmosphere (weather, clouds, precipitation, radiation balance, convective uplift, lightning generation, and ozone chemistry) as well as its effects on the Earth's energy budget. Variations in the amounts of water vapor in the atmosphere are natural and normal, but changes in its vertical distribution may be indicative of changes in the Earth's climate which is of great interest.