The climate is changing: So what?
The Earth’s climate is changing and human activity contributes to it: this is a reality we all need to accept.
The Earth’s climate is changing and human activity contributes to it: this is a reality we all need to accept. But all we hear is a few degrees warmer here and there. What difference does it make for us? Many headline descriptions of climate change refer to global, long-term averages, over timescales that seem irrelevant to our everyday lives. Why should we worry?
The key is to understand the meaning of those large-scale, long-term projections, and the consequences they might have to people’s lives across the world. How are those few degrees going to change to the weather, the environment, and our future?
Changes to weather
One of the hardest things to understand about climate change is the fact that the increase in average global temperatures is predicted to have diverse, and seemingly contradictory effects.
But people like a simple story. Surely increased temperatures mean warmer summers, and the chance to wear skirts or shorts for more than three days of the year? Well maybe, but don’t forget to carry an umbrella…
One of the most obvious and observable effects of rising temperatures is that ice sheets and glaciers are melting – we’ve all seen the photo of a polar bear floating on a tiny raft of ice. While this could lead to loss of habitat and the destruction of some of the most beautiful features of the earth, the melting of snow and glacial ice could actually help communities who rely on melt-water for drinking and sanitation. However, once all the ice has melted, there’ll be no more melt-water, and the higher temperatures mean that less of the melt-water will be replaced by snowfall.
Coming at things from a different angle, high school science tells us that warmer air is able to hold more water vapour, resulting in higher chances of heavy rain. This might sound like an end to droughts and hosepipe bans, but the situation is actually more complex. Changing precipitation patterns could also lead to more frequent periods of water shortage, which without careful management could lead to a boom or bust water supply.
Ultimately we will have to plan for both increased flooding and droughts, through not living in floodplains, constructing buildings with flood-resistant materials, reducing water consumption, and not demanding green lawns like centre court at Wimbledon. Dams and reservoirs are frequently used to manage floods and droughts, but they can increase long-term risk by instilling a false sense of security about their ability to prevent floods and droughts, so preparedness lapses.1
On a more positive note, projections suggest that winter floods in parts of Central Europe,2 Atlantic hurricanes,3 Indian Ocean cyclones,4 and some storms in the Norwegian Sea5 will decrease in frequency. Nonetheless, for some of these storms, when they do form, climate change will make them even more intense.
Changes to oceans, ecosystems, and disease
Rising global temperatures mean that the oceans are also warming up, possibly tempting a few more of you to brave cold waters in your Speedos. But as water warms, it expands, leading to a rise in sea-levels. Around the world, the suggestion for sea-level rise is on the order of one metre higher than today by approximately 2100.6 In addition to low-lying coasts being flooded, higher sea-levels could lead to higher tides, higher waves, and higher storm surges, which will increase coastal erosion and damage harbours and ports (and probably dissuade from that swim after all).
A less obvious cause of change to the oceans is due to carbon dioxide in the atmosphere, which dissolves in water to form carbonic acid. As human activity increases CO2 levels in the atmosphere, more carbonic acid forms in the oceans and acidity increases. Ocean acidification is expected to have severe impacts on delicate marine and coastal ecosystems that cannot tolerate a sudden change in acidity, including coral reefs.7
As global temperatures increase, many species (both on land and in the oceans) are expected to migrate, generally to higher latitudes or higher altitudes in order to seek a familiar climate. Others will adapt in place. The only option for those that can neither adapt nor migrate is to die out and be lost forever. We are right now witnessing a rapid, global mass-extinction, and we can only blame ourselves. 8
These impacts on ecosystems are not only of concern to those of us who are ecologically minded. Even the most indifferent or apathetic might be shocked to know that climate change could have serious implications for human health.
As temperatures rise, parasites and disease-carriers which are normally only found in warm climates, such as malaria, encephalitis, and dengue fever, will be able to tolerate and thrive in higher altitudes and latitudes, bringing new diseases to our doorstep9.
Impacts on a city like London
Anyone who has ever lived in London will know that it is not a city that deals well with normal weather, let alone more variable and extreme weather caused by climate change. During the brief British summer the Underground turns into something resembling a rollercoaster crossed with a sauna, while in winter a light dusting of snow can bring London to it’s knees (or, if you’re not careful, flat on it’s backside). So how will the city, and others like it, cope with the challenges of climate change?
With growing numbers of increasingly hot days ahead, and even potentially with more snow days on the horizon, the disruption and discomfort experienced in London already will increase. Even the seemingly simple task of cooling indoor spaces in summer, and heating them in winter, comes at a cost. While a tax levy could help get the Tube fully air-conditioned, we could also face higher electricity bills as fans and air conditioning become essential in summer, while also having to heat our homes more during winter. Those who cannot afford to do this, particularly the elderly, may even die prematurely. 10
One of the more dangerous dimensions of climate change for London is increased frequency and severity of flooding from the North Sea.12 The Thames Barrier across the river is frequently closed to stop seawater from travelling up the Thames and bursting its banks to flood the capital’s centre. As a result of the feeling of safety imparted by the barrier, Canary Wharf and extensive other developments were constructed, placing vast amounts of assets right in the floodplain.
To keep these locations dry under climate change, the Thames Barrier will need to be closed more often and potentially modified to cope with higher sea levels, disrupting shipping. Even if a near-permanent barrier were needed, alternatives exist for cargo moving up and down the river, such as a transfer dock, or increased use of overland travel. It would be expensive and disruptive, but is easily feasible.
If only it were that simple everywhere…
From the Arctic to tropical islands12
While London and cities of other developed countries have the wealth to attempt to tackle climate change, the irony is that those communities who have least contributed to global warming are also those who will face the toughest challenges.
Arctic indigenous peoples are amongst the groups for whom no easy responses to climate change exist. Their livelihoods, identity, and communities are based on centuries of having built up knowledge and wisdom about their land and environment.
The rapid changes are disorientating, making it difficult for people to rely on their knowledge, experience, and culture, to feed their family. Less reliable sea and land ice around the Arctic can make winter hunting lethal, forcing people to stay indoors and requiring cash for store-bought food. These effects can lead to mental health problems, with traditional knowledge becoming less relevant and fulfilling livelihoods being less available.13
Arctic peoples are also rightly worried about increased industrial and commercial activity around the Arctic, and want assurances that the needs and interests of people already living in the Arctic will be properly taken into account.
Coastal erosion in Alaska linked to climate change is already forcing many communities to plan for relocation.14 Moving an entire community, abandoning your birthplace, and learning about a new environment and location are not easy tasks.
At the other end of the climate spectrum, many low-lying tropical island communities face similar prospects. It is not inevitable that atolls will disappear under sea-level rise and ocean acidification,15 but reduced fresh water access and decreased island stability might force many islanders to move—possibly some entire countries such as Kiribati, Maldives, and Tuvalu.16
The islanders are requesting the power and resources to make decisions on their own terms in their own way.17 They don’t want hand-outs, or to be treated as victims. Instead, as in the Arctic, the tropical islanders have the knowledge, capability, and will, to analyse their own situations and to make their own decisions. Of course putting these decisions into practice requires resources, which the islanders and Arctic peoples argue should be provided by the countries most responsible for climate change.
Most concerning about climate change is what we don’t know. Could all of Antarctica’s and Greenland’s ice melt? If so, then many parts of London and New York would drown along with about half a dozen island countries and much of Bangladesh. Will feedback loops, from clouds to melting permafrost releasing trapped methane, exacerbate or diminish climate change?
One thing we do know is that the unknowns and uncertainties should not block action. As a global society we should be trying to reduce climate change irrespective of climate change. Using less fossil fuels and reversing ecosystem destruction encourages healthier lifestyles and creates a cleaner, healthier, and more enjoyable environment.18
All climate change adaptation activities—for example dealing with extreme temperatures, floods, and droughts—are part of disaster risk reduction, aiming to avoid adverse effects from environmental hazards.19Because disasters still occur regularly, we would need to act more on disaster risk reduction even if climate change were not a concern. We can save lives and avoid the costs of disasters by doing so.20
We know what to do even if we are uncertain about climate change’s exact effects in all places. Let’s start now.