The Reference Antarctic Data for Environmental Research (READER) project data set of monthly mean Antarctic nearsurface temperature, mean sea-level pressure (MSLP) and wind speed has been used to investigate trends in these quantities over the last 50 years for 19 stations with long records. Eleven of these had warming trends and seven had cooling trends in their annual data (one station had too little data to allow an annual trend to be computed), indicating the spatial complexity of change that has occurred across the Antarctic in recent decades. The Antarctic Peninsula has experienced a major warming over the last 50 years, with temperatures at Faraday/Vernadsky station having increased at a rate of 0.56°C decade −1 over the year and 1.09°C decade −1 during the winter; both figures are statistically significant at less than the 5% level. Overlapping 30 year trends of annual mean temperatures indicate that, at all but two of the 10 coastal stations for which trends could be computed back to 1961, the warming trend was greater (or the cooling trend less) during the 1961-90 period compared with 1971-2000. All the continental stations for which MSLP data were available show negative trends in the annual mean pressures over the full length of their records, which we attribute to the trend in recent decades towards the Southern Hemisphere annular mode (SAM) being in its high-index state. Except for Halley, where the trends are constant, the MSLP trends for all stations on the Antarctic continent for 1971-2000 were more negative than for 1961-90. All but two of the coastal stations have recorded increasing mean wind speeds over recent decades, which is also consistent with the change in the nature of the SAM.

A new dataset of monthly and annual mean near-surface climate data (temperature, surface and mean sea level pressure, and wind speed) for the Antarctic region has been created using historical observations [Scientific Committee on Antarctic Research (SCAR) Reference Antarctic Data for Environmental Research (READER)]. Where possible, 6-hourly surface synoptic and automatic weather station observations were used to compute the means. The ability to quality control the data at the level of individual observations has produced a more accurate series of monthly means than was available previously. At the time of writing, the mean data are available on the Internet (http://www.antarctica.ac.uk/met/programs-hosted.html). Data for 43 surface-staffed stations and 61 automatic weather stations are included in the database. Here, mean temperature, pressure, and wind speed data for 19 occupied stations with long records are provided.

In a changing climate it is important to understand how all components of the climate system may change. For many impact sectors, particularly those relating to flooding and water resources, changes in precipitation intensity and amount are much more important than changes in temperature. This study assesses possible changes in extreme precipitation intensities estimated through both quantile and return period analysis over Britain. Results using a regional climate model (with greenhouse gas changes following the IS92a scenario for 2080 -2100) indicate dramatic increases in the heaviest precipitation events over Britain. The results provide information to alter design storm intensities to take future climate change into account, for structures/projects that have long life times. Copyright

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An assessment is made of the climate simulations from the NCEP (National Centers for Environmental Prediction) Reanalyses over Europe. This assessment was initiated as part of the European Commission funded study on Atmospheric Circulation Classification and Regional Downscaling (ACCORD) and was designed to test the suitability of the Reanalyses for this type of application. Here NCEP Reanalyses (pressure, temperature and precipitation) from 1958 through 1997 are compared to station data of precipitation and temperature and composites of mean sea level pressure (MSLP) data. The comparison is made over a European window using monthly data with a focus on 3 land areas: Central and Eastern England and Italy, where daily timescale data are employed. MSLP data are generally well simulated; however, an input problem in the NCEP data prior to 1967 results in unrealistically low surface pressure. NCEP surface pressure over Greenland is also shown to be unrealistically high during the winter months. Spatially NCEP MSLP is shown to correlate quite well with UK Meteorological Office (UKMO) MSLP over the ocean and much of northeast Europe, while they correlate less well over high orographical regions. It is shown that, while daily temperature is well simulated, daily precipitation is less so, particularly during the summer months when convective precipitation is dominant. Total precipitation over the 2 UK areas is lower than observed, by as much as 22% over Central England. The number of rain day events is underestimated over the 3 regions, although the anomaly of rain per rain day is shown to vary between the regions, being overestimated in NCEP in Eastern England and Italy. Mean daily temperature is shown to be much better simulated compared with precipitation, with a slight warm bias in all 3 grid boxes.