Manchester city centre could be 1.5 degrees cooler despite global warming if 10% more green spaces were added. — Manchester city centre could be 1.5C (2.7F) cooler despite global warming if 10% more green spaces were added. Photograph: Alamy Photograph: Alamy

How green spaces could stop cities from overheating

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A 10% increase in green space in our cities could help to keep temperatures at present levels into the 2050s, despite climate change

Most city-dwellers are big fans of green spaces, with the benefits to health and community well-being evident in the data. There's more to it though - adding more commons, parks and greens could also shelter British cities from the full effect of global warming.

Since the beginning of the 20^th century global temperature has increased by 0.8C (1.44F), with two thirds of warming occurring since 1975. Temperature increase from now until 2050 is expected to be increasingly rapid, with human activity the dominant cause of warming.

Climate change is set to bring hotter, drier summers over the next three decades with urban dwellings - already generally warmer than rural areas - due to take the brunt. This is because roads, pavements and buildings absorb a relatively high amount of heat.

As Britian gets hotter, this 'urban heat island effect' will bring with it extra drought and extended periods with high temperatures for our cities.

By 2050 the extreme readings associated with current heatwaves are expected to be the norm while by the end of the century they may even seem mild.

How could green space reduce the impacts of climate change?

The data highlights that an increase in green spaces within UK cities, including trees, parks, gardens, green roofs and waterways, could help to combat future increases in temperature.

This is despite the fact that, at least in England, there has been a relatively drastic cut in the financial support for England's parks and open spaces.

Focusing upon Greater Manchester, one of the most populous city in the UK, a10% increase in green space could keep temperatures at or below present levels into the 2050s, despite a changing climate.

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Across Greater Manchester on average, the temperature will increase by 1.4C (2.5F) from baseline to 2050 as a result of climate change, from 21.8C (71.24F) to 23.2C (73.8F). This is a substantial rise of over 6%. The map above shows how the temperature would expect to increase within the city currently.

An increase of 10% in cooling green space within the city over the same period could maintain temperatures at existing levels, with temperature only increasing by 0.1C (0.18F) 2050. The map below shows the change in temperature if green space within the city increased as described previously.

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It may even substantially reduce temperatures. If it was implemented there is a predicted decrease of 1.5C (2.7F) in the city centre of Manchester for 2050 where existing green space is lowest.

Investment in green space within urban areas in the UK could help to prevent the expected discomfort, health risks and increased mortality associated with rising summer temperatures in the UK.

Current and forecasted temperatures for Greater Manchester

The map below shows the baseline temperature (average for 1961-1990) for Greater Manchester. The second map shows the forecasted temperatures for 2050.

The temperature data used is from the UK Climate Projections 2009 (UKCP09) which are designed to help communities to adapt to climate change. The projections have been continuously updated with evolving climate science.

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It uses the most likely of the UK climate projections for 2050, a 'high emissions scenario' with a 50% probability. This is compared to average or 'baseline' temperatures for the period 1961-1990. The temperature values are summer temperatures that will occur on the two warmest days of the year.

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The data was generated using the STAR Tools, a tool developed by the University of Manchester and The Mersey Forest available and can be used to generate similar data for other locations in the UK.

This article was amended on May 22. It previously miscalculated the fahrenheit change. All figures shown should now be correct.