Energy and carbon, global heating and climate change
Climate change is the result of global heating, caused by human activity, mainly by burning coal, oil and gas. This has become a very urgent problem. We all need to reduce our contribution to climate change, and do it fast.
That includes saving energy; both to try and help mitigate climate change, and to conserve energy and save costs.
Even in the era of coronavirus, we think climate change remains the most threatening environmental threat we face. It tends also to get pushed down the agenda by political controversies, and the constant search for economic growth.
A stream of reports from United Nation (UN) agencies, the World Meteorological Agency (WMO) and the UK’s Committee on Climate Change (CCC) have made clear that time is very short. Climate change may well be slipping past the point of no return.
The most important reports are those of the Intergovernmental Panel on Climate Change (IPCC). These are issued every 6-8 years. The latest IPCC report on the science of climate change was published in 2021-’22, in three huge volumes. They are unsparing in their conclusions. It is ‘unequivocal’ that human activity is causing global heating, which must be curbed for the sake of humanity and all of Nature.
So, the science of climate change is rock solid, beyond reasonable doubt. The underlying physical processes have been known for 200 years. Research over the last 40 years has built up an overwhelming body of evidence.
Causes of climate change
Climate change is caused by a sustained trend of global heating (we used to call it ‘global warming’, until it began to speed up dramatically and dangerously).
This global heating results from a physical/chemical phenomenon known as the ‘greenhouse effect’.
The causes of this are primarily due to human activity, especially emissions of greenhouse gases (known as GHGs), mostly carbon dioxide or CO2. This comes from:
- Use of energy from coal, oil and gas (‘fossil fuels’) by factories and power stations, buildings, cars and aeroplanes;
- Land use change including cutting down and burning trees and forests;
- Many foods and agricultural practices (fertilisers, irrigation, cattle rearing, transport and refrigeration).
Building products such as cement, steel and aluminium also make a contribution.
The heat content of the planet’s surface, lower atmosphere and ocean is increasing at a speed unprecedented since prehistoric times!
The global average rise since pre-industrial times is now about 1.1 degrees Celsius. That might not seem like much, but it is just an average. Added up over the whole world that’s a lot of extra heat! Increasingly, many places are experiencing dangerous heat waves and other weather extremes.
- From the 1970s until the 2000s, average temperatures were rising steadily; the rise in surface temperatures slowed for a few years; then in late 2014, temperatures started rising again, sharply. 2015-2021 were the seven warmest years ever recorded;
- 2014 was probably the then warmest year ever recorded, 2015 easily surpassed it, then 2016 beat the annual record yet again – three record years in a row; 2020 was equal warmest with 2016;
- 2019 and 2021 saw numerous all-time temperature records crashing; in at least four northern European countries, in Canada and Siberia, all-time records have been topped by 2-5 deg C;
- A warmer climate means, generally, a wetter climate. More rain leads to frequent flooding (in the UK, and much more seriously in many other countries, including Germany, Belgium and China in 2021); in contrast, extended dry periods occur too, leading to drought and famine;
- More and more, warming is causing wildfires – in California, Southern Europe, Australia, and even in the Arctic! Glaciers are melting in mountain ranges, with sea ice around the poles, and the Greenland icecap – for the first time, rain (instead of snow) has been recorded in central Greenland;
- Global heating has harmful consequences for many species and ecosystem; in particular, warming of the oceans causes the bleaching and death of coral reefs.
The greenhouse effect and greenhouse gases (GHGs)
The greenhouse effect is like a blanket of gases in the atmosphere, which let sunlight in but then trap some of the heat.
The main GHGs are water vapour and carbon dioxide (CO2). These are natural and healthy in themselves: animals (including humans) breathe CO2 out, plants breathe it in. That still leaves some in the air.
This quantity of CO2 is relatively small, but very significant. When the atmosphere contains the right concentration, it stays more or less within temperatures suitable for life as we know it to go on. When there is too much, as now, this upsets the natural balance and causes the earth to warm up.
The atmospheric concentration of CO2 is now over 420 parts per million (ppmv), having risen from only 280ppmv during industrial times – a 50% increase. This change is caused by our emissions. Not only have our emissions continued to soar, but also there are signs that the capacity of the biosphere to absorb them may be decreasing as plants and the ocean become saturated.
Absorption of CO2 by the oceans causes them to become more acidic (strictly speaking, less alkaline). This has harmful effects on for example the formation of the shells of coccolithophorids (a kind of ocean plankton).
Is it all natural cycles?
Yes there are complex natural cycles; no they are not the cause of global heating.
Of course there are irregular ups and downs in the temperature and the weather, in different places – locally, individual heat waves or freezing winters don’t always reflect the global trend.
But over longer periods or larger areas, the effects of increasing warming are dominant, and getting more and more severe.
The warming problem is further reinforced by feedback effects, for example due to deforestation, and the melting of the Arctic:
- Once forests are gone, there are fewer trees left to breathe in CO2;
- The warming itself releases more CO2 and water vapour from the oceans; this adds to the heating effect;
- The Arctic is warming especially fast – as the ice melts there is less to reflect sunlight back into space, so the heat goes straight into the ocean.
So what can be done?
In December 2015, the UN’s annual summit of nearly 200 countries (known as COPs), held that year in Paris, finally reached agreement in broad terms on how to deal with climate change. This ‘deal’ is now in force. The USA withdrew but later re-joined. Almost every country on earth is now signed up – maybe the only thing everyone agrees on!
It isn’t a perfect deal, much more needs to be done, but it is a huge step forward.
COP26 took place in November 2021 in Glasgow. This finalised the 2015 Paris agreement. It aimed to secure strengthened commitments from countries round the World, and had some success in that regard though with very regrettable last-minute compromises.
There are two international targets for limiting global heating:
- To limit the increase to within 2 degrees Celsius above the pre-industrial average;
- To make every effort to stay below 1.5 deg C above the pre-industrial average.
The second of these targets is looking more and more likely to be exceeded.
Intergovernmental panel on climate change (IPCC)
Regular IPCC reports are published every 6-8 years. These reports each come in three weighty volumes. The latest report began to be published in 2021, with the Physical Science volume (more than 3000 pages), and a summary of about 40 pp. These showed that:
- It is unequivocal that human behaviour is changing the climate;
- The impacts of climate change are already being felt in every region across the globe (temperate regions are not safe);
- These impacts will continue to get worse, the longer we continue to burn fossil fuels (coal, oil and gas);
- Every tonne of CO2 (the gas mainly emitted by burning fossil fuels) makes a difference – whether that’s a tonne emitted or a tonne not emitted.
In 2018, on the request of the signatories to the Paris agreement, the IPCC also published a challenging report on what we all need to do to keep warming to less than 1.5 deg C (now widely thought to be the necessary target), and what are the implications for sustainable development.
Further reports have been issued in 2019 by the IPCC and the World Meteorological Organisation (WMO), about the effect of global heating on glaciers and icecaps, and about changes in weather patterns worldwide. These reports make clear we are facing an escalating crisis.
The UK and Church of England
In response to the IPCC’s 2018 report, the UK government tightened its long-term target radically, now aiming to achieve ‘net zero carbon’ standard by 2050. This followed the advice of the national Committee on Climate Change. ‘Net zero carbon’ means that we need to remove from the air (eg by planting trees) at least as much as we put into it.
The General Synod of the Church of England, in line with many local authorities and other organisations, resolved in February 2020 to set a target of Net Zero Carbon by 2030. In March 2020, London Diocese Synod adopted a revised Diocesan Environmental Policy, affirming and adopting General Synod’s motion.
The Diocese of London
The Diocese of London is among many faith groups and other organisations seeking to give a lead.
The Diocese’s environmental efforts are directed, first and foremost, to reducing greenhouse gas emissions from our own buildings – carbon dioxide (CO2) mainly.
Because the Diocese has also adopted the Church of England’s Net Zero Carbon target, it is necessary and urgent for us to attend to our buildings and how we heat and light them.
Our own response
Ultimately it is our own individual actions that cause global heating and climate change. This results in increasing human suffering.
In developed countries like the UK, many people have insurance which is a big help. Otherwise the result is shattered lives. In some places – eg the Diocese’s partners in Mozambique and many others – people may remain flooded out for years.
Whatever the outcome, we should do all we can to help deal with it – let’s be part of God’s solution.
Energy and fossil fuels
Traditionally we have relied on fossil fuels to provide our energy. Most London churches are heated using gas, a few still run on oil.
Electricity is also used to provide heat, as well as lighting and power. UK grid electricity is becoming much less carbon intensive, due to phasing out coal and a big increase on the contribution of renewable energy.
Fossil fuels all result in greenhouse gas emissions. Coal is worst by far; although this is now being rapidly replaced in the UK (for electricity generation at least), regrettably it is still used for steel production.
Moves are now afoot to introduce renewable biomethane, and even a proportion of hydrogen, into the gas grid. The intended benefits of hydrogen depend on how it is produced – from methane (‘blue hydrogen’), or water (‘green hydrogen’). The latter is likely to be much more climate friendly.
Cutting our energy use
Increasing use of renewable energy is very much needed. We should still be thinking about solar panels on our churches. All our churches should be switching to green energy suppliers, for electricity at least.
At the same time, we need to cut our energy use. Of course we should bear in mind health and fuel poverty – an ageing population needs more heat and can less afford it. Nevertheless there are many ways for churches, companies and individual people to avoid waste and reduce consumption.
Diocesan Environmental Policy
Climate Action Programme
Climate Action Projects
Green Energy Suppliers.
Intergovernmental Panel on Climate Change (IPCC)
World Meteorological Organisation (WMO)
UK Committee on Climate Change.
Environment and Sustainability, front page.