Volume 1: Summary of Research -
Executive Summary
Climate change
Recent trends
Global climate data analysed by the Hadley Centre shows that 2001 was
the second warmest year for the last 142 years. Nine of the 10 warmest
years on record occurred between 1990 and 2001, of which only 1998 was
warmer than 2001. Central England temperature data records show that 2001
was 0.46°C warmer than the 1961-1990 average.
Simulations performed by the Hadley Centre showed that climate change
in the second half of the 20th century cannot be attributed to solar variability.
Even with enhanced solar variability, the models fail to reproduce 20th
century trends unless anthropogenic forcing is also included.
The Climate Research Unit at the University of East Anglia also found
that trends in summer temperature data cannot be explained by natural
variability.
Measurements of greenhouse gases at Mace Head in Ireland have shown that
baseline concentrations of many of the gases reached the highest background
concentrations ever recorded in 2000, the latest year for fully validated
data.
As a Party to the United Nations Framework Convention on Climate Change
(UNFCCC), the UK has more than met its commitment to return emissions
of carbon dioxide and all other greenhouse gases to 1990 levels by the
year 2000, with emissions falling over this period by 13.2% for all greenhouse
gases and 7.5% for CO2 . The UK also has a target under the
Kyoto Protocol to reduce a basket of six greenhouse gases to 12.5% below
1990 levels by 2008-2012; and a domestic goal of a 20% reduction in carbon
dioxide emissions below 1990 levels by 2010.
Emission projections for all greenhouse gases, analysed by economic sector
and by gas, were reported in the UK's Third National Communication to
the UNFCCC (published in 2001), and the UK's Climate Change Programme
(published in 2000). It is estimated that the policies and measures outlined
in these reports could reduce the UK's greenhouse gas emissions to 23%
below 1990 levels by 2010 and carbon dioxide emissions to 19% below 1990
levels by 2010. The UK's carbon dioxide emissions could fall still further,
through the impact of other measures that cannot be quantified, allowing
the 20% goal to be achieved. A formal review of the programme will be
conducted in 2003/4.
The UK met its annual inventory reporting requirements to the UNFCCC
and to the European Union for the period 1990 to 2000. Regional greenhouse
gas inventories were produced for the period 1990-1999 for England, Scotland,
Wales and Northern Ireland.
Future climate change
The Hadley Centre's ground-breaking carbon-climate model has shown that
carbon cycle feedback could strongly accelerate global warming. Experiments
with different scenarios show that stabilisation of carbon dioxide concentrations
in the atmosphere require larger than predicted cuts in emissions if this
feedback is included.
The Hadley Centre's regional model was used to simulate retrospectively
the extreme precipitation associated with the floods in late 2000. The
accurate simulation of that event gives added credence to simulations
of the future, which predict that extreme precipitation events such as
the floods, which currently occur approximately every 20 years, can be
expected every 2-3 years by the end of the century.
A ''climate prediction index'' is under development and will provide
a way of measuring the ability of models to simulate the present day climate
and subsequently identify the best models for making predictions of future
climate.
Intergovernmental Panel on Climate Change (IPCC)
The Technical Support Unit (TSU) at the Met Office continued to support
Working Group I of the IPCC, until Sir John Houghton's retirement as UK
co-chair of the Group in April 2002. The TSU prepared the WGI contribution
to the IPCC Third Assessment Report on Climate Change, which was published
in 2001, and also prepared the Synthesis Report, which addressed the policy
relevant climate issues. UK scientist Professor Martin Parry was elected
as co-chair of WGII in April 2002, and a new TSU has been set up at the
Met Office, to provide support for this Group.
The Advanced Along Track Scanning Radiometer (AATSR) was launched at
the end of February 2002 on the Envisat satellite and is already sending
back excellent data on sea surface temperatures.
The data will be used to monitor trends in the climate.
Impacts of climate change
The UK Climate Impacts Programme (UKCIP) was set up in 1997, to encourage
private and public sector organisations to assess their vulnerability
to climate change, so that they can plan their own adaptation strategies.
Recent studies include the impacts of climate change on health, water
demand, biodiversity and the built environment. Regional studies to assess
impacts in Northern Ireland, Yorkshire and Humberside were also completed.
Newly updated climate change scenarios for the UK, developed by the Tyndall
Centre, using predictions from the Hadley Centre Regional Climate Model
(RCM), were launched in April 2002.
The scenarios are the first to combine internationally agreed IPCC emissions
scenarios with a high resolution regional model.
The new climate change scenarios indicate that:
- Annual temperature averaged across the UK may rise by between 2 and
3.5°C and some areas could warm by as much as 5°C by the 2080s;
- Heavy winter rainfall events that occur every 2 years are expected
to increase in intensity by between 5 and 20%; and
- Relative sea-level around the UK could rise perhaps by as much as
86 cm in southern England by the 2080s, with extreme sea levels being
experienced more frequently.
The Climate Impacts LINK project disseminates Hadley Centre results to
the larger climate research community and provides support for other users.
Recently the LINK project has assisted with the distribution of European-level
data associated with the 2002 UKCIP scenarios.
Projects to assess the regional impacts of climate change on a range
of issues (for example, agriculture, water resources and human health),
in India and on Chinese agriculture have commenced in collaboration with
their respective governments.
Stratospheric ozone layer
The Antarctic ozone 'hole' reached a record 28 million km2 in 2000, subsequently
decreasing to 26 million km2 in 2001, in 2002 the 'hole' was even smaller.
The variation in size is thought to be due to meteorological factors.
Significant depletion is still expected to occur from time to time over
the next decade but slow recovery should take place as levels of ozone
depleting substances decline in response to controls under the Montreal
Protocol.
Continued monitoring of ozone levels at Lerwick and Camborne indicated
the occurrence of three low ozone events in the UK during the period July
2000 to the end of March 2002.
Total ozone values at Lerwick and Camborne showed a consistent drop in
levels, between 1980 and 1999, of approximately 4-6%. However, it now
appears as though values at Camborne are levelling out whilst values at
Lerwick have continued to decrease.
Continued monitoring of solar ultraviolet (UV) radiation at sites in
Manchester and Reading have not yet indicated any clear trend in solar
radiation reaching Earth's surface at these locations.
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