As the world's leaders come together to discuss climate change, cooling must be part of the debate around global warming. Cooling is currently part of the worsening problem, but it could become an important part of the solution.
Take Phoenix, Arizona, to illustrate environmental challenge of cold. Phoenix exists, in its current form, because of air conditioning. In buildings and transport, artificial cooling makes Phoenix, like many other desert cities, liveable.
But as the planet warms, the demand for air conditioning will grow. Estimates suggest that by 2060 the amount of energy used to cool buildings will surpass the amount used on heating.
America uses more electricity to run its air conditioning than Africa uses on everything. Generating that electricity creates greenhouse gas emissions, which further warm the planet, causing more of us to install air conditioning and so on.
And in Phoenix we are seeing a more localised phenomenon. Air conditioning creates cold indoors, but simultaneously it pumps out heat into the atmosphere. Studies have shown that the cumulative effect of all this cooling is a localised warming of the night air by about 1 degree.
That might not sound very much, but Phoenix is only one of hundreds, if not thousands of cities fighting to stay cool. And air conditioning is only one of many applications of cooling. The warming effects of cold are very serious.
The problem is also growing rapidly. A warming, an increasingly wealthy world mean that the global demand for cooling is growing.
Take refrigerators - with wealth comes fridge ownership. Over 95% of urban households in China now have fridges, compared to only 7% 20 years ago. That is a process that is being replicated around the world. Millions of new fridges create substantial additional demand on the energy system, but the effects are also more far reaching.
Newly affluent middle classes in Asia, Africa and South America expect exactly the same lifestyle as those of us in Europe or America. That that includes access to food that often travels large distances, but retains its quality.
Refrigerated trucks are going to become as common a sight on the streets of Jakarta and Delhi as they are in London or Berlin. Currently between two and four million refrigerated trucks operate globally - a figure is predicted to rise to over 15 million by 2025.
At present, those trucks predominantly rely on polluting diesel engines to keep their cargo cool. These not only add to poor air quality, but also contribute to global warming.
Cold sits at the nexus of global challenges of food, water and energy. Greater proliferation of refrigeration will help to reduce food loss, to feed growing populations and conserve natural resources. It can have a positive impact around the world.
But unless we can move to clean cold technologies and systems, we will create catastrophic environmental consequences.
To meet the demand for air conditioning predicted by the end of the century requires 2.6M wind turbines, up from only 260,000 in operation today. No matter how hard we try, it will be almost impossible to decarbonise cooling just by decarbonising electricity. We have to change the way we generate cold, as well as the way we generate power.
The good news is that new approaches, innovative technologies and resource efficient systems are beginning to take hold. Only last month the University of Birmingham outlined its recommendations for how we can grasp the opportunity to 'do cold smarter'.
Change is undoubtedly coming. To break the negative cycle of cooling leading warming, cold must be on the agenda of global climate change talks.
We can transform cold from part of the problem, to part of the solution for a warming world.Suggest a correction