Causes of climate change
Natural causes or human activity
A variety of factors, both natural and human, can influence the earth’s climate system. The world's climate varies naturally as a result of:
- the relationship between the ocean and the atmosphere
- changes in the earth's orbit
- changes in energy received from the sun
- volcanic eruptions
There is now strong evidence and broad-based agreement that major global warming cannot be explained just by natural changes. Those seen over recent years and those which are predicted over the next century, are thought to be mainly as a result of human behaviour.
The greenhouse effect
The earth is surrounded by a layer of gases which act like the glass walls of a greenhouse: they let the sun’s rays enter, but stop much of the heat from leaving. This is a natural process, and it is this layer of ‘greenhouse gases’ (mainly carbon dioxide and water vapour) that keeps the planet warm enough for people and animals to live.
However, as we give out more greenhouse gases into the atmosphere, the greenhouse effect becomes stronger. More heat is trapped, and the earth's climate begins to change unnaturally.
Climate change in Northern Ireland
In Northern Ireland, disruption to business, services and people's daily lives will increase if adverse changes occur.
An increased risk of flooding and coastal wear will put pressure on drainage, sewage, roads, water and habitat.
Increased temperature, increased pollution and poorer air quality may bring discomfort to the vulnerable and threaten species of animals and crops.
In Northern Ireland, the main sources of greenhouse gas emissions are:
- agriculture (27 per cent) - for example methane releases from livestock and manure, and other gases from chemical fertilisers
- transport (23 per cent) – there is a reliance on road use in Northern Ireland
- energy (17 per cent) - the use of fuel to generate energy (excluding transport)
- residential use of fuel (13 per cent) - the energy used in your home (the main use is heating)
Other things in people's homes contribute to climate change indirectly. Everything, from furniture to computers, from clothes to carpets, uses energy when it is produced and transported – and this causes emissions to be released. Reusing and recycling instead of throwing items away will mean less waste and less energy needed to make new items.
Preparing for climate change
UK climate change projections, published in 2018 (UKCP18), set out a range of possible outcomes over the next century, based on different rates of greenhouse gas emissions into the atmosphere.
UKCP18 projects greater chance of hotter, drier summers and warmer, wetter winters with more extreme weather and rising sea levels. The highest predicted releases for Northern Ireland shows that by:
- 2070 winters could be up to 3.9 °C warmer and summers could be up to 4.9°C hotter
- 2070 winters could be 25 per cent wetter and summers 38 per cent drier
- 2100 sea levels in Belfast could rise by up to 94cms
Changes you can make to your home
There are many things you can do to protect your home and yourself.
Make sure your home is well insulated to keep you warm in winter and cool in summer.
Windows and ventilation
Cool your home naturally instead of using air conditioning, which can damage the environment:
- create a breeze by opening the windows at the highest and lowest points or on opposite sides of the house
- open windows at night and close windows, curtains or blinds during the day
- when replacing windows, ask about special coatings that reflect or absorb heat
More ways to keep cool
- fit blinds, shutters or awnings to provide shade and keep heat out
- paint outside walls and roofs a light colour to reflect heat
- replace carpets with solid flooring like stone or ceramic tiles which have a cooling effect and can lessen damage from a flood
- use household appliances at cooler times of day
Preparing for floods and droughts
Check if your home is at risk of flooding by viewing the Rivers Agency's Strategic Flood map. Consider ways to keep floodwater out, such as fitting air brick covers or installing a waterproof membrane on the outside walls. Also check the condition of your guttering and drains.
As the UK is likely to experience more droughts in summer months, saving water will become even more important.
- Saving water in the home
- Flood maps NI - Department for Infrastructure website
- Flooding in your area
Changes you can make to the outside of your home
If you have space outside your house, there are ways to keep your home cool and help prevent a flood.
Planting deciduous trees in your garden (particularly on the south-facing side) can shade your house in summer and allow sun to shine through in winter when the leaves have fallen.
You can buy root barrier membranes to protect a patio or house foundations from damage caused by roots.
- Shade planting - Royal Horticultural Society website
- Plant selector - Royal Horticultural Society website
Saving water in the garden
Using less water in the garden will help to make the most of resources, especially during drier months.
Don't pave over gardens
Paving over gardens contributes to flooding, as hard surfaces like concrete or block paving take in less rainwater than lawns and plants.
Harder materials also store more heat from the sun and this can make a difference to temperatures, especially in urban areas.
If you need to create space for parking outside your house, use materials like lawn or gravel, which absorb rainwater, leaving just two paved tracks for the car. You can buy recycled gravel and paving that allows water to soak through.
You might need to get planning permission to alter your garden, particularly if you’re going to use materials that don’t let water soak through.
Green or living roofs
Grow plants and vegetation on rooftops, after properly preparing the surface with soil and root barriers.
Green roofs can:
- help prevent floods by absorbing rainwater
- lower the temperature of buildings during summer and keep them warmer in winter
- support wildlife, including bees
Placing potted shrubs and plants on flat roofs can also help.
You should ask the opinion of a structural engineer before taking on a green roof project for your house, to make sure it can support the extra weight without causing damage.