Salinity and Porosity of Laboratory Grown Young Pancakes By Hayley H. Shen Clarkson University, Potsdam, NY USA Karl-Ulrich Evers Hamburgische Schiffbau-Versuchsanstalt, Hamburg Germany Stephen F. Ackley, Mingrui Dai Clarkson University, Potsdam, NY USA and Jeremy Wilkinson Scottish Association for Marine Science, Scotland UK ABSTRACT An indoor experiment to study pancake ice growth in a wave field has been conducted in the ARCTECLAB of the Hamburgische Schiffbau-Versuchsanstalt (HSVA). This unique facility was equipped with two distinct wave tanks in the same cold room. Two wave makers were operated independent of each other in two identical flumes. Pancake ice growth was monitored in these two separate wave tanks. In addition to the two wave tank tests, we also grew ice under calm water condition in the same room using a box with insulated walls and bottom. Each test began with open water condition. The duration of each test was about 7 hours long. This report summarizes our salinity and porosity measurements of the ice samples collected during the tests. The salinity values were found to be much higher than previously reported from field studies. There was no field porosity data that could be found in the literature to compare with. INTRODUCTION Ice formation is associated with salt or brine rejection. Brine rejected during ice growth can cause intense localized water mass modification by increasing the salinity of the upper waters. If the resulting saline water is denser than the water below it becomes unstable and is liable to sink. The sinking of the high saline water is generally thought to occur via plumes. Associated with the downward transport of water is also an upward transport of water of the same volume. These vertical currents are responsible for energy, momentum, chemical and biological species redistribution in the ocean. Furthermore in a few areas of the world e.g. Greenland Sea and Weddell Sea the sinking can occur to great depths. These regions ventilate the deep ocean, influence the carbon cycle and drive thermohaline circulation of the world ocean. Hence salinity enhancement through ice production and growth in the ocean has many important implications. (Gordon et al., 1993, Wepperning et al., 1996). Direct measurement of salt ejection when ice is forming is difficult to perform. Alternatively, salt content in the ice cover can be measured. The difference between the salt content in the ice cover and that in the ambient water column is the amount of salt produced from ice formation. Ice production is an integral part of the global hydrological cycle. The production of ice may be estimated from the ice cover thickness if the porosity is known. Like salinity, ice porosity is also an important parameter. When the porosity is sufficiently