Policy 5.10 Urban Greening
A The Mayor will promote and support urban greening, such as new planting in the public realm (including streets, squares and plazas) and multifunctional green infrastructure, to contribute to the adaptation to, and reduction of, the effects of climate change.
B The Mayor seeks to increase the amount of surface area greened in the Central Activities Zone by at least five per cent by 2030, and a further five per cent by 2050.
C Development proposals should integrate green infrastructure from the beginning of the design process to contribute to urban greening, including the public realm. Elements that can contribute to this include tree planting, green roofs and walls, and soft landscaping. Major development proposals within the Central Activities Zone should demonstrate how green infrastructure has been incorporated.
D Boroughs should identify areas where urban greening and green infrastructure can make a particular contribution to mitigating the effects of climate change, such as the urban heat island.
 Mayor of London. Leading to a Greener London. GLA, 2009
5.50 The Mayor has an ambitious programme to plant another 10,000 street trees by 2015, and wishes to see an additional two million trees in London by 2025 to help with both mitigation of and adaptation to climate change. Urban greening is also a key element of the much broader Climate Change Adaptation Strategy, which encourages the use of planting, green roofs and walls and soft landscaping. The research undertaken in the LUCID programme (The Development of a Local Urban Climate Model and its Application to the Intelligent Design of Cities) has worked towards providing information on reductions in temperature in London that could be achieved by the addition of different types of urban greening.
5.51 London experienced a heatwave in 2003 that killed at least 600 people and its impact was exacerbated by the urban heat island effect. Cooling the urban environment through the use of green infrastructure, as part of a package of measures to combat climate change, will have important health and social benefits. It is particularly important to address the urban heat island effect in central London. Further work will be undertaken to establish a methodology by which major developments can be assessed for the contribution that they will need to make to increasing green infrastructure in the Central Activities Zone. Research undertaken in Manchester has shown that increasing urban green space by 10 per cent can help to cool high density areas of the city by around three to four degrees centigrade. Urban greening also contributes to achieving a network of green multifunctional infrastructure across London with the consequent range of benefits that this can bring (see Policy 2.18).
 Climate Change and Cities: the Role of Green Infrastructure. Built Environment: Volume 33, Issue 1, 2007