A global climatology of wind–wave interaction

Generally, ocean waves are thought to act as a drag on the surface wind so that momentum is transferred downwards, from the atmosphere into the waves. Recent observations have suggested that when long wavelength waves, characteristic of remotely generated swell, propagate faster than the surface wind momentum can also be transferred upwards. This upward momentum transfer acts to accelerate the near-surface wind, resulting in a low-level wave-driven wind jet. Previous studies have suggested that the sign reversal of the momentum flux is well predicted by the inverse wave age, the ratio of the surface wind speed to the speed of the waves at the peak of the spectrum. ECMWF ERA-40 data has been used here to calculate the global distribution of the inverse wave age to determine whether there are regions of the ocean that are usually in the wind-driven wave regime and others that are generally in the wave-driven wind regime. The wind-driven wave regime is found to occur most often in the mid-latitude storm tracks where wind speeds are generally high. The wave-driven wind regime is found to be prevalent in the tropics where wind speeds are generally light and swell can propagate from storms at higher latitudes. The inverse wave age is also a useful indicator of the degree of coupling between the local wind and wave fields. The climatologies presented emphasise the non-equilibrium that exists between the local wind and wave fields and highlight the importance of swell in the global oceans

Metacaspase gene function in the mushroom fungus Schizophyllum commune

The overall goal of this project was to investigate the biological role of a putative metacaspase gene present in the mushroom fungus Schizophyllum commune. For this study, we have utilized a strain of S. commune that is unable to integrate DNA via the non-homologous end joining pathway. This forces transforming DNA to integrate homologously, as is required for the purposes of gene knockout. The gene Scp1 encodes a likely member of the metacaspase protein family, which are suspected to have activity similar to caspases, the latter crucial to programmed cell death. A knockout construct containing a non-functional version of Scp1 was previously generated in our laboratory. This DNA was then transformed into Schizophyllum commune in an attempt to knockout the native Scp1 gene. At present a likely knockout (null) strain has been identified, and analysis by polymerase chain reaction has supported its status as a true knockout. A homozygous null mutant of Scp1 will then be generated, and will be compared to a wild-type strain for any alterations in colony growth and/or mushroom development. The role(s) of other members of the metacaspase family will eventually be examined by a similar approach