But help is at hand.
Ten key terms
1.5 degrees
Keeping the rise in global average temperature rise below 1.5 degrees Celsius will avoid the worst impacts of climate change, scientists say
That's compared with 'pre-industrial times'. The world has already warmed about 1C since then
Climate change
A pattern of change affecting global or regional climate, as measured by average temperature and rainfall, and how often extreme weather events like heatwaves or heavy rains happen.
This variation may be caused by both natural processes and by humans. Global warming is an informal term used to describe climate change caused by humans.
Carbon footprint
The amount of carbon emitted by an individual or organisation in a given period of time, or the amount of carbon emitted during the manufacture of a product
Carbon neutral
A process where there is no net release of CO2. For example, growing biomass takes CO2 out of the atmosphere, while burning it releases the gas again
The process would be carbon neutral if the amount taken out and the amount released were identical. A company or country can also achieve carbon neutrality by means of carbon offsetting
Emissions
Emissions are any release of gases such as carbon dioxide which cause global warming, a major cause of climate change
They can be small-scale in the form of exhaust from a car or methane from a cow, or larger-scale such as those from coal-burning power stations and heavy industries
Feedback loop
In a feedback loop, rising temperatures on the Earth change the environment in ways that affect the rate of warming
Feedback loops can be positive (adding to the rate of warming), or negative (reducing it)
As the Arctic sea-ice melts, the surface changes from being a bright reflective white to a darker blue or green which allows more of the Sun's rays to be absorbed. So less ice means more warming and more melting
Global warming
The steady rise in global average temperature in recent decades, which experts believe is largely caused by human-produced greenhouse gas emissions
The long-term trend continues upwards, scientists say, even though the warmest year on record, according to the UK's Met Office, is 2016
Geo-engineering
Geo-engineering is any technology that could be used to halt or even reverse climate change
Examples range from extracting carbon dioxide from the atmosphere and storing it underground to more far-fetched ideas such as deploying vast mirrors in space to deflect the Sun's rays
Some scientists say geo-engineering may prove essential because not enough is being done to reduce emissions of greenhouse gases
Others warn that the technologies are unproven and could have unforeseen consequences
IPCC
The Intergovernmental Panel on Climate Change is a scientific body established by the United Nations and the World Meteorological Organization
Its role is to examine and assess the latest scientific research into climate change. Its report in 2018 warned that the rise in global temperatures should be limited to 1.5C to avoid dangerous impacts
Runaway climate change
Describes how climate change may suddenly get worse after passing a 'tipping point', making it even harder to stop or reverse
In 2018, the IPCC said that global emissions must be reduced by 45% by 2030, and to net zero by 2050 to have 50% chance of limiting temperature rises to 1.5C this century
