The rates at which gases exchange between the oceans and the atmosphere are extremely important to global biogeochemical cycles and to predicting and modelling future climate change, but quantifying them accurately currently remains elusive. Some important issues requiring accurate estimates include the rate at which anthropogenic carbon dioxide can be taken up by the oceans and quantifying the marine sources of other important climate active gases such as dimethyl sulphide that scientists believe control cloud formation over the oceans. We plan to measure concentrations of DMS in the water so that we can use this data, together with a new technique for measuring the air-sea flux of DMS to be made by our project partners from the University of Hawaii, in order to better understand the processes that control the transfer of gases between the atmosphere and the ocean. We think that as well as the wind, the amounts of bubbles made by breaking waves will have an important impact on air--sea gas exchange. Much of the data on the amount of DMS that is present in seawater is collected from water pumped into research ships from the bottom of the ship. This is usually at a depth of about 5-8m. However, in order to calculate the amount of DMS that is transferring from the sea to the air we really need to know the concentration of this gas at the sea surface. Everybody assumes that the concentrations measurements from the ship's hull (ie 5-8m) are the same as those made at the sea surface. However, we know that DMS is produced and consumed by biological processes in the water and that it is rapidly destroyed by sunlight. We therefore want to check whether there is a difference between dimethyl sulphide concentrations at the sea surface compared to the depths of ship hulls. This would be have important consequences for calcuating the actual amount of dimethyl sulphide that the ocean supplies to the atmosphere. It is also important to know if there are any gradients when we want to compare the direct estimates of the DMS flux with the indirect estimates as this would impact on how important we think the bubbles might be in air-sea gas transfer. We plan to participate in a research cruisein the North Atlantic Ocean in the suimmer of 2007 when there will be many other groups making a variety of key measurements and observations (measure seastate, whitecapping and wave breaking and evaluating the role of bubbles and surfactants air-sea gas exchange.

The oceans have a major influence on the composition of our atmosphere and therefore on the climate that we live in. This is because significant quantities of important climate-active gases exchange between the oceans and the atmosphere. Understanding the rates at which these gases transfer across this interface is important for society in general because it enables us to improve the accuracy of mathematical models that predict global climate change. Dimethyl sulphide (DMS), produced by microbes in the surface oceans is the major source of sulphur to the vast, remote marine atmosphere. In the atmosphere it contributes to the formation of aerosols and clouds, reducing the amount of radiation reaching Earth. So it actually cools the planet, as opposed to carbon dioxide (CO2) and other greenhouse gases. We will join forces with a research group from the University of Hawaii to quantify the sea-to-air exchange rate of DMS on an expedition to the Southern Ocean. This high-profile expedition is funded and organised by the US National Oceanographic and Atmospheric Administration (NOAA) and will involve a suite of measurements focusing on gas exchange between ocean and atmosphere. Ours is a critical piece of research because: 1. DMS has its greatest influence on climate in remote regions such as the Southern Ocean; 2. The high winds and waves that exist in the Southern Ocean will allow us to untangle some of the key issues concerning air/sea gas exchange, particularly the impact of bubbles and breaking waves; and 3. the Southern Ocean is a major sink for anthropogenic CO2 and the information we will learn from studying DMS exchange rates will tell us a great deal about the controls on how fast CO2 enters the oceans from the atmosphere. The results of this work will be published in high-quality scientific journals. This information will be valuable to climate scientists and will ultimately improve the accuracy of assessments of Global Change for policy makers and the public.

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United States

Honeybees supply man with honey and provide a vital pollination service. However, recently a large number of colonies have died unexpectedly. Although the reasons for this remain unexplained, scientists believe that the parasitic honeybee mite Varroa destructor, and its ability to transmit honeybee viruses, is a major factor. A hidden problem is that the world-wide spread of Varroa may have permanently altered the viral landscape within which honeybees and other insects now operate. In areas where Varroa is now well established, certain honeybee viral pathogens are almost ubiquitous and, worryingly, have been found in native bees, wasps and bumblebees in several countries, therefore posing a wider biodiversity threat. However, almost nothing is known about the viral landscape before Varroa arrived, since the mite had already spread world-wide before the molecular tools required to detect the viruses were developed. The very recent spreading of the Varroa mite across the Hawaiian Islands provides a rare opportunity to study how Varroa is affecting the viral landscape, load and strain virulence. By collecting viral data from honeybee colonies, native bees and wasps before the spread of Varroa will allow us for the first time to compare viral patterns pre- and post-Varroa at both local and global scales. This will provide insights into the population dynamics and evolutionary consequences of the introduction of a new viral transmission route. Although these data are vital to understand host-parasite co-evolution between the honeybee-Varroa mite and viral pathogens, it will also shed light onto the wider issue of how such invasive pests may threaten biodiversity indirectly, by potentially changing the wider viral landscape.