Chathuranga Jayarathne

To investigate the sensitivity of evaporation to changing long-wave radiation we developed a new experimental facility that locates a shallow water bath at the base of an insulated wind tunnel with evaporation measured using an accurate digital balance. The new facility has the unique ability to impose variations in the incoming long-wave radiation at the water surface whilst holding the air temperature, humidity and wind speed in the wind tunnel at fixed values. The underlying scientific aim is to isolate the effect of a change in the incoming long-wave radiation on both evaporation and surface temperature. In this paper, we describe the configuration and operation of the system and outline the experimental design and approach. We then evaluate the radiative and thermodynamic properties of the new system and show that the shallow water bath naturally adopts a steady-state temperature that closely approximates the thermodynamic wet-bulb temperature. We demonstrate that the long-wave radiation and evaporation are measured with sufficient precision to support the scientific aims.

To investigate the sensitivity of evaporation to changing longwave radiation we developed a new experimental facility that locates a shallow water bath at the base of an insulated wind tunnel with evaporation measured using an accurate digital balance. The new facility has the unique ability to impose variations in the incoming longwave radiation at the water surface whilst holding the air temperature, humidity and wind speed in the wind tunnel at fixed values. The underlying scientific aim is to isolate the effect of a change in the incoming longwave radiation on both evaporation and surface temperature. In this initial paper we describe the configuration and operation of the system and outline the experimental design and approach. We then evaluate the thermodynamic properties of the new system and demonstrate that the evaporation, air temperature, humidity and wind speed are measured with sufficient precision to support the scientific aims. We find that the shallow water bath naturally adopts a steady state temperature that closely approximates the thermodynamic wet bulb temperature.

To investigate the sensitivity of evaporation to changing longwave radiation we developed a new experimental facility that locates a shallow water bath at the base of an insulated wind tunnel with evaporation measured using an accurate digital balance. The new facility has the unique ability to impose variations in the incoming longwave radiation at the water surface whilst holding the air temperature, humidity and wind speed in the wind tunnel at fixed values. The underlying scientific aim is to isolate the effect of a change in the incoming longwave radiation on both evaporation and surface temperature. In this initial paper we describe the configuration and operation of the system and outline the experimental design and approach. We then evaluate the thermodynamic properties of the new system and demonstrate that the evaporation, air temperature, humidity and wind speed are measured with sufficient precision to support the scientific aims. We find that the shallow water bath naturally adopts a steady state temperature that closely approximates the thermodynamic wet bulb temperature.

To investigate the sensitivity of evaporation to changing longwave radiation we developed a new experimental facility that locates a shallow water bath at the base of an insulated wind tunnel with evaporation measured using an accurate digital balance. The new facility has the unique ability to impose variations in the incoming longwave radiation at the water surface whilst holding the air temperature, humidity and wind speed in the wind tunnel at fixed values. The underlying scientific aim is to isolate the effect of a change in the incoming longwave radiation on both evaporation and surface temperature. In this initial paper we describe the configuration and operation of the system and outline the experimental design and approach. We then evaluate the thermodynamic properties of the new system and demonstrate that the evaporation, air temperature, humidity and wind speed are measured with sufficient precision to support the scientific aims. We find that the shallow water bath naturally adopts a steady state temperature that closely approximates the thermodynamic wet bulb temperature.

To investigate the sensitivity of evaporation to changing longwave radiation we developed a new experimental facility that locates a shallow water bath at the base of an insulated wind tunnel with evaporation measured using an accurate digital balance. The new facility has the unique ability to impose variations in the incoming longwave radiation at the water surface whilst holding the air temperature, humidity and wind speed in the wind tunnel at fixed values. The underlying scientific aim is to isolate the effect of a change in the incoming longwave radiation on both evaporation and surface temperature. In this initial paper we describe the configuration and operation of the system and outline the experimental design and approach. We then evaluate the thermodynamic properties of the new system and demonstrate that the evaporation, air temperature, humidity and wind speed are measured with sufficient precision to support the scientific aims. We find that the shallow water bath naturally adopts a steady state temperature that closely approximates the thermodynamic wet bulb temperature.