Climatic Research Unit : About CRU

History of the Climatic Research Unit

CRU Directors The Climatic Research Unit (CRU) was established in the School of Environmental Sciences (ENV) at the University of East Anglia (UEA) in Norwich in 1972. The contribution of the Founding Director, Professor Hubert H Lamb, cannot be overstated. Hubert Lamb's determination and vision can only be appreciated against the view, generally prevailing within the scientific establishment in the 1960s, that the climate for all practical purposes could be treated as constant. The weather changed from day-to-day, from week-to-week, and season-to-season. There was interannual variability, but over years (the perceived argument went) a constancy was reliably evident. It is now recognised that the climate is not constant, but changes on timescales which are of relevance to humanity and its social and economic systems. Hubert Lamb, encouraged by the support of Keith Clayton and Brian Funnell, Deans of ENV around the time, made the brave decision in 1971 that his pioneering work on climate change would be best conducted at a university.

Many climatologists will now say that CRU's work in these early years played a major part in navigating the study of climate change out of an academic backwater and started to set the agenda for the major research effort in, and political preoccupation with, climate research since. The purpose of this brief history is to document some of these achievements by subject, in a loose chronological order. A list of all the staff and students is given here.

Hubert Lamb retired as Director in 1978. He was succeeded by Tom Wigley (to 1993), Trevor Davies (1993-1998), Jean Palutikof and Phil Jones (jointly from 1998 to 2004) and Phil Jones (to the present). Each has brought their own specialities to bear in guiding CRU through what have been generally good times as far as successful funding is concerned, but occasionally through fallow periods.

Since its inception in 1972 until 1994, the only scientist who had a guaranteed salary from ENV/UEA funding was the Director. Every other research scientist relied on 'soft money' - grants and contracts - to continue his or her work. Since 1994, the situation has improved and now three of the senior staff are fully funded by ENV/UEA and two others have part of their salaries paid. The fact that CRU has and has had a number of long-standing research staff is testimony to the quality and relevance of our work. Such longevity in a research centre, dependent principally on soft money, in the UK university system is probably unprecedented. The number of CRU research staff as of the end of July 2007 is 15 (including those fully funded by ENV/UEA).

The early priority of CRU was set against the backdrop of there having been little investigation before the 1960s of past climatic changes and variability, except by geologists and botanists, although there was an excess of theories. The objective of CRU, therefore, was "to establish the past record of climate over as much of the world as possible, as far back in time as was feasible, and in enough detail to recognise and establish the basic processes, interactions, and evolutions in the Earth's fluid envelopes and those involving the Earth's crust and its vegetation cover". The early efforts towards this objective were the interpretation of documentary historical records. This was painstaking and challenging work and progressed through the 1970s.

In 1979, CRU hosted a remarkable, international, interdisciplinary conference (Climate and History), a turning point for the future work on historical climatology and the influence of climate on human societies. This type of work still has an important place in CRU's research portfolio to the present day, although it has broadened to include the development and analysis of early instrumental records and the extension of important climate indicators and datasets as far back in time as possible. A second international conference again focussing on historical climate variations and their links with societal change, but with a view to future changes and interactions, was held in 1998. An almost complete list of CRU publications is given here, including the volumes resulting from these two conferences.

Global Air Temperature The area of CRU's work that has probably had the largest international impact was started in 1978 and continues through to the present-day: the production of the world's land-based, gridded (currently using 5° by 5° latitude/longitude boxes) temperature data set. This involved many person-years of painstaking data collection, checking and homogenization. In 1986, this analysis was extended to the marine sector (in co-operation with the Hadley Centre, Met Office from 1989), and so represented the first-ever synthesis of land and marine temperature data - i.e., the first truly global temperature record, demonstrating unequivocally that the globe has warmed by almost 0.8°C over the last 157 years. This work continues year-on-year to update and enhance the record and its publication is eagerly awaited around the world. The most recent innovation has been the development of a comprehensive set of error estimates at the grid-box and larger scales (see Brohan et al. 2006 Adobe Portable Document Format fileand IPCC AR4 chapter 3 Adobe Portable Document Format file).

Besides the global temperature data set, there has been much CRU effort devoted to the compilation of a comprehensive, quality-controlled precipitation data base. This, together with CRU's high-resolution (0.5° by 0.5°) monthly datasets (for maximum and minimum temperature, precipitation, rainday counts, vapour pressure, cloudiness and wind speed) for all the world's inhabited land areas, has provided many researchers, in the UK and overseas, with their basic data for a whole range of studies. It is likely that CRU ranks only behind NCEP/NCAR, ECMWF (ERA-40) and NCDC as the acknowledged primary data source by climate scientists around the world.

The vast potential of tree rings to provide annually-resolved climate reconstructions over thousands of years has been exploited by the application of rigorous statistical methods to tree-ring data. In collaboration with a num­ber of institutions throughout the world - in particular through a strong association with the Institute of Forest, Snow and Landscape Research in Birmensdorf, Switzerland - CRU is now regarded as one of the world's foremost exponents of dendroclimatology. On longer time scales, the first rigorous quantification of past climate from the distributions and assemblages of beetle remains was made. Understanding the past has always been a primary aim of CRU, and until recently was mainly only of academic interest. Placing the instrumental period in a longer context has provided renewed interest in proxy climate reconstruction. CRU was the first to develop a time series (based on tree-ring and other proxy climate data) of average Northern Hemisphere summer temperatures back 1000 years. This showed that the world is probably now at its warmest. Milder centuries were evident at the beginning of the millennium, with markedly cooler ones in the 17th and 19th centuries, but the average temperature for the period since 1975 is likely unprecedented during the past millennium. (see IPCC AR4 chapter 6 Adobe Portable Document Format file)

Another research topic explored in the early days of CRU was the Southern Oscillation and its connections to the climate around the globe. This was amongst the first work to be undertaken on this phenomenon since its original identification by Sir Gilbert Walker in the 1920s, and presaged the later, enormous attention which would be paid to the El Niño Southern Oscillation (ENSO) phenomenon. Research here is still ongoing and has expanded to other major modes of atmospheric and ocean circulation variability (the Northern and Southern Annular Modes, North Atlantic Oscillation, North Pacific Oscillation, Pacific Decadal Oscillation and the Atlantic Multidecadal Oscillation). CRU's work in this area has extended many of the indices, assessed the influence (sometimes of a variable nature) of the phenomena on surface climate variability and evaluated how well the phenomena and their climate impacts are modelled by Global Climate Models.

As it became clearer, in the 1980s, that the world was warming, a question that was asked with increasing frequency was how much, if any, of the warming was a consequence of human activity? CRU had made an important contribution to the posing of that question, so was in an excellent position to attract some more research funding to address it. The UK Government became a strong supporter of climate research in the mid-1980s, following a meeting between Prime Minister Mrs Thatcher and a small number of climate researchers, which included Tom Wigley, the CRU director at the time. This and other meetings eventually led to the setting up of the Hadley Centre for Climate Prediction and Research, within the Met Office. At the same time, other governments were also taking notice and wanted more information. As this need was not being met by international scientific bodies and institutions at the time, they set up the Intergovernmental Panel on Climate Change (IPCC). This was under the United Nations Framework (later the UN Framework Convention on Climate Change, UNFCCC) and led to assessments being produced in 1990, 1995, 2001 and 2007. CRU staff have been heavily involved in all four assessments, probably more than anywhere else relative to the size of an institution (see IPCC AR4 Authors). The most recent IPCC assessment report (in 2007) has stated - "The warming of the climate system is unequivocal".

In the late 1980s, CRU started to explore the pattern correlation "fingerprint" method of detection, a technique to assess how the observed pattern of climate change matches that which can be attributed to particular causes. This work culminated in 1995, when a team of researchers from American institutes and from CRU, using the computer simulations of climate change caused by increasing emissions of carbon dioxide, the most important greenhouse gas, and sulphate aerosols (developed by the Lawrence Livermore National Laboratory, USA), was able to detect the effects of these climate forcing factors in the climate observations. The results were in stark contrast to the consensus view expressed by IPCC in 1990, when it was stated that the effect of increased carbon dioxide concentrations could not yet be identified in the observed record. This work played a critical role in the conclusion reached by the 1995 assessment of the IPCC that "the balance of evidence suggests that there has been a discernible human influence on global climate". Subsequent IPCC reports have strengthened these statements (in 2001: "there is new and stronger evidence that most of the warming observed over the last 50 years is attributable to human activities" and in 2007: "most of the observed increase in globally averaged temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations") and led most governments, industries, multi-national companies and the majority of the public to accept that the climate is warming, and humans are part of the cause. Accepting the evidence is one thing, but not all governments appreciate the full scale of the problem yet.

CRU has also played a major role in attempts to predict future anthropogenic climate change, and some of its consequences. In the late 1970s, rapid advances were being made elsewhere in atmospheric climate modelling (using Global Climate Models, GCMs), but it would be many years before these could be coupled to ocean GCMs. CRU pioneered simpler models (Energy Balance Models, EBMs) and, unlike the computer-intensive GCMs, they allowed the consideration of the consequences of a wider range of future emission scenarios and an assessment of the uncertainties due to parameters such as the climate sensitivity. Even though the GCMs have now improved in scope and speed, these simpler models are still valuable for interpolating between, or extrapolating beyond, the results of GCMs. CRU's work with these models led directly to the global-mean temperature projections given by the IPCC in 1990 and to corresponding projections of sea-level rise.

In 1992, CRU conducted a comprehensive integrated assessment of the climate projection problem, linking an EBM (now called MAGICC) and ice-melt models with models for translating greenhouse gas emissions to atmospheric concentrations and sulphur dioxide emissions that could be used to drive MAGICC. This work by CRU was the first attempt to consider the full spectrum of anthropogenic influences on climate in an internally consistent way. This methodology has improved, but the same basic approach is still used and remains a vital tool used by the IPCC in the construction of future climate projections, as it is able to cover a much wider range of the uncertainties in greenhouse gas and aerosol scenarios than the more computationally expensive GCMs. The dramatic increases in computer power over the last 30 years have mainly been used to increase the spatial and vertical resolution of GCMs and to simulate many more aspects of the climate system (e.g., interactive atmospheric chemistry, interactive biosphere, runoff routing). Earth System Models or Global Environmental Models (as GCMs are sometimes called) require the largest and fastest computers in the world. These resources are best allocated to improving the comprehensiveness of the models, as opposed to running extensive scenario combinations for IPCC reports every few years. MAGICC and other similar developments around the world, therefore, continue to fill an important niche.

CRU researchers have also pioneered several approaches to the construction of regional climate change scenarios which can be used in climate impact assessments, environmental planning and climate policy debates. These approaches included some of the first analogue scenarios and the development of techniques for linking results from simple and complex climate models. In the 1990s, CRU incorporated model-based scenarios into integrated assessments of climate change undertaken for the UK, European and US governments. This work has led to the creation of several scenario software applications which are widely used by the research communities. This scenario work has also been incorporated into IPCC reports.

Much scenario work is dependent on translating the broad-scale climate information produced by GCMs and their regional counterparts (RCMs) to a space- or time-scale which is of relevance for impact assessment (e.g., catchment or station scale and day-to-day weather). CRU pioneered some of the first work on this crucial issue of "downscaling", both from a statistical (using observed relationships between space- and time-scales) and dynamical (directly through RCMs) approach and was among the first to thoroughly compare the two approaches. Scenarios are becoming more and more detailed, and to incorporate all aspects of uncertainty (emissions, model parameterization, etc.) and different modelling frameworks (also called structural uncertainty), the next, emerging, generation is largely based on probability density functions. The UK is leading the way in these endeavours, but comprehensive education of the impacts community in the use and interpretation of probability-based information is required. CRU is taking the lead here with probability-based projections based on adapting weather generators to provide daily data (see CRANIUM project) within the next set of national scenarios (UKCIP08).

This field has also led to much work in the climate impacts field, which has become gradually more extensive to support the discussion of mitigation and adaptation options. This moved the agenda from the scientific determination of the global warming problem to how to solve the problem. In the late 1990s, the UK Research Councils recognized the need for a centre to address these issues. CRU, ENV and other groups across the UK were successful with their bid, and the Tyndall Centre for Climate Change Research was born in 2000. The Tyndall Centre focuses on solutions to the problem of climate change, while CRU continues to work on all aspects of climate science. CRU and Tyndall work together on some projects, but their specific aims and agendas are different. The growing practical applicability of CRU work is nonetheless reflected in the increasing range of academic users, stakeholders, decision makers and professional bodies with which CRU is involved, as well as the range of impacts sectors covered. The latter include agriculture, water, health, energy and, most recently, the built environment. These aspects of CRU work in the UK are also facilitated by strong links with the UK Climate Impacts Programme (UKCIP) which was set up in 1997 - based at the University of Oxford.

From 1992-2007, CRU co-ordinated or played a key role in the Climate Impacts LINK Project, whose purpose is to disseminate the results of current climate simulations and future climate projections from the Hadley Centre's computer models to research groups in the UK and overseas, who are concerned with attempting to assess the impacts of climate change. The objectives of the LINK project are to ensure that all such groups are aware of the nature of such results, that they cannot be used uncritically, and, most importantly, that the same standard climate data sets are used as input to the many impact assessments that have been undertaken. This latter objective has helped to make the results of different impact assessments comparable, enabling a large part of the full range of potential uncertainties to be incorporated into the UKCIP08 framework of probability-based projections. A measure of the success of the LINK project in making consistent sets of past and future climate information available to non-experts, together with appropriate education and advice, is that the majority of studies to date addressing impacts of climate change around the world have used data from Hadley Centre climate models. The LINK project became the mould for data dissemination from climate modelling centres and it eventually led to the establishment by the IPCC of the Data Distribution Centre (DDC). Both projects are now led by the British Atmospheric Data Centre (BADC), but CRU is still involved.

A main thrust of the Unit's research programme since the early 1980s has, therefore, been global warming: the human contribution, the future climate response, and possible impacts of future climate change, with an increasing emphasis on adaptation to these impacts. But this was not to the exclusion of other research, much of it of commercial relevance. A few examples follow. From the late 1970s through to the collapse of oil prices in the late 1980s, CRU received a series of contracts from BP to provide data and advice concerning their exploration operations in the Arctic marginal seas. Working closely with BP's Cold Regions Group, CRU staff developed a set of detailed sea-ice atlases, covering estimates of data quality and climate variability as well as standard climatological means, and a series of reports on specific issues, such as navigation capabilities through the Canadian Archipelago. Assessment of the wind energy resource over the UK led to the development of predictive schemes to assess the potential power production at candidate wind turbine sites. Research on predicting canopy wetness as a vector for disease in cocoa plantations has been of special interest to Brazilian cocoa producers. Advice from CRU has been sought on far-future climate states in relation to the long-term safety of low- and intermediate-level radioactive waste storage sites. On shorter-term timescales, work on extreme events with implications for nuclear power station operation has been undertaken. Perhaps, not surprisingly, the insurance and re-insurance industries have been a regular sponsor of research with studies evaluating the risk of hurricane landfall on the Gulf and Atlantic coasts of the US, the impacts of severe storms in Europe and the characteristic of the typhoon risk over Japan. Former public utilities, such as the Central Electricity Generating Board (and latterly National Power) commissioned work from CRU on acid rain, wind energy, and surface ozone. Work has also been undertaken for Friends of the Earth and Greenpeace.

Returning to the beginning, Hubert Lamb's work during the early 1970s on historic North Sea storm surges contributed in no small part to the implementation of plans for a flood barrier on the River Thames, drawn up after the disastrous East Coast floods of 1953. The number of times the Thames Barrier has been closed since its completion - increasingly so in recent years because, as Lamb predicted, sea level has risen - testifies to the value of this research. Hubert Lamb's other ground-breaking research (much of it summarised in the two volumes of his landmark book Climate: Present, Past and Future, which appeared during the 1970s) is still widely cited in science articles today.

Today, CRU is still dependent upon research grant income to maintain the size and breadth of our research and student communities. The European Commission of the European Union (EU) provides the largest fraction of our research income under the Environment and Climate Change Programme. Since the mid-1990s, CRU has co-ordinated 9 EU research projects and been a partner on 16 others within the 4th, 5th and 6th Framework Programmes. Although EU funding is very important, we also endeavour to maintain the diverse pattern of funding reflected by the research described in this "history of CRU" and in the list of Acknowledgements below.

Since its inception in 1972, over 40 students have been awarded PhD degrees, and the rate of awards has dramatically grown in the last 10 years. Today, CRU has a thriving student community of 11 PhD students (July 2007). CRU also runs a NERC-recognized Master of Science degree programme on Climate Change. For the past 10 years, this degree attracted between 6 and 10 students per year, but the last two academic years (2005/06 to 2006/07) have seen an upsurge to 22 students per year. This is a strong endorsement of the growing importance of the subject and of our reputation.

A number of CRU staff have been awarded medals, certificates or fellowships from the Royal Meteorological Society, the European Geosciences Union, the American Meteorological Society, the American Geophysical Union and the Leverhulme Trust. Over the last 35 years also, several staff have been on the editorial boards of a number of major climatic journals ( International Journal of Climatology, Climatic Change, Weather, Atmospheric Science Letters, Journal of Climate, The Holocene, Boreas, Climate Research, Theoretical and Applied Climatology ).

A research unit this size doesn't run itself. The Directors and Research Staff over the years have been supported by a number of administrative, secretarial and other support staff, although this number has fallen in the last decade due to changes in working practices, organisation and information technology. This technology, however, doesn't manage or maintain itself. CRU foresaw at the birth of personal computers that a permanent staff member was vital to keep everyone going and keep them up-to-date. In the early days this was difficult to justify on research grants, but Mike Salmon is now on the ENV support staff and manages CRU computers and in a large part of ENV. He also manages our web site - 'which as ever reigns supreme' according to the New Scientist.


This list is not fully exhaustive, but we would like to acknowledge the support of the following funders (in alphabetical order):
British Council, British Petroleum, Broom's Barn Sugar Beet Research Centre, Central Electricity Generating Board, Centre for Environment, Fisheries and Aquaculture Science (CEFAS), Commercial Union, Commission of European Communities (CEC, often referred to now as EU), Council for the Central Laboratory of the Research Councils (CCLRC), Department of Energy, Department of the Environment (DETR, now DEFRA), Department of Health, Department of Trade and Industry (DTI), Eastern Electricity, Engineering and Physical Sciences Research Council (EPSRC), Environment Agency, Forestry Commission, Greenpeace International, International Institute of Environmental Development (IIED), Irish Electricity Supply Board, KFA Germany, Leverhulme Trust, Ministry of Agriculture, Fisheries and Food (MAFF), National Power, National Rivers Authority, Natural Environmental Research Council (NERC), Norwich Union, Nuclear Installations Inspectorate, Overseas Development Administration (ODA), Reinsurance Underwriters and Syndicates, Royal Society, Scientific Consultants, Science and Engineering Research Council (SERC), Scottish and Northern Ireland Forum for Environmental Research, Shell, Stockholm Environment Agency, Sultanate of Oman, Tate and Lyle, UK Met. Office, UK Nirex Ltd., United Nations Environment Plan (UNEP), United States Department of Energy, United States Environmental Protection Agency, Wolfson Foundation and the World Wildlife Fund for Nature (WWF).