In many ways, climate change is all about water. Higher temperatures and more intense storms have significant impacts - the effects of water – too much, too little, in the wrong place, at the wrong time - are serious.
The international community is preparing to thrash out a new agreement on greenhouse gas emissions at COP21. LSx and Londoners are making personal pledges to change things in our own lives and in our city - London. Many of our pledges are about water: using less, recycling more, reducing leakage. How does changing our ways with water in London help solve the problem of climate change?
Responses to climate change are usually divided into two categories. Mitigation is about reducing emissions to slow down and stop the impact humans are having on the climate – for example, switching from fossil fuels to renewables, or using less energy. Adaptation is about preparing for the impacts of climate change – for example, air conditioning on the tube, or strengthening our flood defences. Managing water more sustainably in London will helpprevent and prepare for climate change.
When we’re standing under the shower, doing some laundry or washing up, climate change mitigation is hardly the first thing on our minds - we need to get to work, or make sure we have clean shirts or cups in the morning. But when we use hot water we are using energy - and producing carbon emissions.
Heating water is the second largest use of energy in our homes after heating the house itself. Treating and pumping water from our rivers to get it to our homes and then pumping and treating our sewage uses a lot of energy. Water is heavy, and cleaning dirty water to make it safe for people and the environment also uses a lot of energy. If we use less water, we use less energy, we reduce our carbon emissions - and we help slow down climate change.
Climate change is unlikely to have much impact on London’s annual average rainfall, but it will change when the rain falls during the year. Wetter winters and drier summers are predicted from 2050 on – and London may suffer more drought and floods.
If we use less water there is more water to go around. Given population projections of around 10 million Londoners by 2050, improving water efficiency and recycling water are vital to securing London’s water supply in the future. Thames Water are investigating recycling water into their supply, fixing leaks in their network and improving water efficiency. We need more incentives for developers and householders to do the same. A strong lead is required from the Mayor and central government.
Green infrastructure must be a central feature of how London adapts to climate change. Increasing the number of trees, green roofs, ponds, permeable paving, rain gardens and other features has multiple benefits. They help to deal with bigger downpours, soaking up rainwater before it floods our homes and drains. They also help cool the city and improve people’s mental and physical wellbeing.
Find out more about how to use less water with:
Waterwise http://www.waterwise.org.uk/pages/save-water.html and
Thames Water http://www.thameswater.co.uk/save-water/9696.htm
The Landscape Institute http://www.landscapeinstitute.org/policy/GreenInfrastructure.php
Take one of our COP21 pledges and sign the LSx petition asking Thames Water to reduce leaks - http://www.lsx.org.uk/news/hottopics.aspx?id=3660
Written by Sarah Bell, University College London