David leads part of the Climate Monitoring and Attribution group, developing in situ climate data since the Industrial Revolution and remotely-sensed data for the satellite era.
Areas of expertise:
Variations and trends of climate observed in the past 300 years.
The Central England Temperature series.
Influence of urban warming on the global temperature record.
Correcting biases in sea-surface and upper-air temperatures.
Influence of ocean temperatures on rainfall in the African Sahel.
David is a Scientific Manager in the Climate Monitoring and Attribution group, developing observational data mainly for the atmosphere but with some involvement with oceanic data. His team of research scientists works on diverse aspects of observed climate variability and change in the atmosphere.
Currently, David and his team work on daily temperature and precipitation worldwide, especially extremes; surface humidity and heat stress worldwide; temperature and precipitation in the United Kingdom; remotely sensed atmospheric temperature and moisture profiles, especially in the tropics; and mean sea level pressure and atmospheric circulation. Regular contributions are made to the planning, maintenance and improvement of the Global Climate Observing System (GCOS) and David has provided guidance to the GCOS/World Climate Research Programme Atmospheric Observation Panel for Climate. Observational requirements for monitoring and seasonal prediction over Africa have been assessed and an initial assessment of global precipitation data sets is to be made in 2013/14.
David has helped develop and improve the 350-year Central England Temperature (CET) data set, and a paper on the uncertainties in the early part of the CET record has been published. David has also been involved in assessing the impact of urban heat islands on estimates of global warming; these impacts are found to be small, because we, and groups outside the Met Office, have largely avoided urban sites, or applied adjustments to any urban data used.
Initial attempts have been made to use the model-based 20th Century Reanalysis to assess the quality of, and interpolate gaps in, the Met Office/University of East Anglia HadCRUT surface air temperature data set.
David has worked in the Met Office since 1968. Initial work in tropical meteorology included the 1974 Global Atmospheric Research Programme's Atlantic Tropical Experiment. Since 1978 David has researched into worldwide climatic variations and trends, with some involvement in monthly and seasonal forecasting, in collaboration with Met Office and external partners in the UK and worldwide. A key theme has been sea surface temperature, including the development of adjustments to the data to compensate for changes in observing techniques, to allow climatic trends since the 19th century to be estimated reliably. Marine air temperature and mean sea level pressure data were also improved and analysed. Sea surface temperatures were used to explain and predict variations in seasonal rainfall in the African Sahel. Another key theme has been the improvement of worldwide radiosonde balloon data to attempt better analysis of climatic variations aloft. For the UK, Gordon Manley's monthly Central England temperature record since 1659 has been updated, and a daily series has been constructed back to 1772, ensuring that the data are not biased by urban warming or site-changes. David has been involved in all the scientific assessments of the Intergovernmental Panel on Climate Change (IPCC), and a lead-author of 3 of these, as well as a member of two United States panels reporting on progress in understanding temperature changes aloft. Ongoing climate research and monitoring require high-quality unbiased observations worldwide, which David and his team are pursuing in their current research.