The Committee on Climate Change has released its second UK Climate Change Risk Assessment Evidence report, explaining the risks and opportunities facing the country due to climate change and setting out priorities for the next five years.
The 2,000-page report took three years to compile and like its 2012 predecessor predicts more flooding, heatwaves, water and food shortages, soil degradation and air pollution. But it also adds new concerns including the risk to "culturally valued" structures and sites such as historic houses and gardens. Extreme weather already affects historic gardens and structures "but there is a lack of information on the scale of current and future risks, including for historic urban green spaces and gardens", the report points out. "Cultural heritage is a valued resource and impacts from environmental changes need to be assessed over long timescales based on adequate monitoring."
But "although some strategic planning, risk assessment work, case and scoping studies have been done ... and there is some understanding of how climate change might affect historic building materials ... there is little or no systematically collected quantitative information on the level of current and future risk for the UK's historic building stock and their surroundings or historic urban green spaces and gardens", such as Royal Parks. "The lack of monitoring data, surveys and analysis may lead to the loss or degradation of cultural assets and their social value."
Previous research into the impacts of climate change on gardens has highlighted reduced frosts, earlier onset of spring, increased winter rainfall and flooding as well as summer droughts and changing pests and diseases. Lawns will become hard to maintain, while historic layouts and plant collections established in cooler, less flood-prone times may not survive a warmer future, according to 2002 research project Gardening in the Global Greenhouse: The Impacts of Climate Change on Gardens in the UK. Eight of the warmest UK years on record have occurred from 2000 onwards.
The Committee on Climate Change's report also points out that a warming climate will cause faster vegetative growth and longer seasons, which could be a boon for the agriculture and forestry sectors if they can manage constraints such as water availability and soil fertility. But the committee warns that faster growth could have implications for tree management, especially with more violent and frequent storms felling more trees.
Climate change may bring some silver linings for the parks and garden sector as people spend more time outdoors and active travel such as walking and cycling becomes popular, the report suggests. As populations migrate into cities, parks and green infrastructure will become increasingly essential. But the report also highlights the shrinkage of urban green space in England (a seven per cent fall between 2001 and 2013, two-thirds of which was caused by paving over household gardens), meaning more surface water flooding and heat islands that will impact on people's health as well as infrastructure safety.
Planning policy in England does not specifically address urban heat islands, though the National Planning Policy Framework does call for planners to promote environmental quality and health and maintain urban green space, the report adds. Planning policies in Northern Ireland, Scotland and Wales are more explicit in calling for green space to reduce heat islands.
But the report criticises all four countries for failing to make use of recent evidence that there are other greening interventions that are effective cooling measures. "Potential win-win measures" such as green roofs and walls should be used to not only cool but provide other climate-mitigating benefits such as flood and pollution reduction and improving biodiversity.
The report also outlines the benefits of sustainable urban drainage systems and the failure of the planning system and developers to adopt such measures. It berates the Government for not addressing the barriers to uptake identified by the 2008 Pitt Review, such as the automatic right of developers to connect to sewers and questions over who pays for maintenance.
The report will inform the Government's second climate change risk assessment, which is due in January 2017. The Government's National Flood Resilience Review is due by the end of July.
Risks - parliamentary committee lists key climate change issues
The six most urgent risks, according to the adaptation subcommittee for the Committee on Climate Change:
? Flooding and coastal change.
? Health, well-being and productivity at risk from
? Water shortages for public use, agriculture,
energy generation and industry, with impacts on freshwater ecology.
? Risk to natural capital, including soils and biodiversity.
? Risks to food production and trade.
? New and emerging pests and diseases as well as invasive non-native species.