COP26: Can countries be forced to meet net zero targets? And more questions
The COP26 climate summit is under way in Glasgow - one of the biggest ever world meetings on how to tackle global warming.
BBC News Reality Check correspondent Chris Morris and environment correspondent Matt McGrath answer some of your questions.
You can send a question using the form at the bottom of this page.
Is there a way to force countries in the UN, especially China and India, to cut back to net zero by 2050? Can sanctions or similar trade restrictions be used against them? Diana Butungi, Kampala
Chris Morris writes:
Only a few countries have made their net zero pledges legally binding. Many of the national pledges are non-binding targets, but there is a hope that as momentum towards net zero begins to accelerate it will provide an incentive for others to follow.
It would be possible in theory to impose trade or other sanctions on countries that are moving more slowly, but that could be counter-productive. The focus of meetings like COP26 is to try to encourage international cooperation.
It's also unfair to put all the blame on countries like India and China for the majority of carbon emissions, even though China is the largest emitter of carbon dioxide in the world today and India is the third largest. China and India have huge populations, and much lower emissions per person than more developed countries.
In any case, it's important to consider the historical role played by European countries and the United States which are responsible for far more cumulative emissions than China or India.
The damaging effects of emitting CO2 into the atmosphere linger for hundreds of years, and the rich world has acknowledged that it has the primary responsibility for tackling climate change.
Are there plans for governments and countries to invest in carbon-capture technologies on a very large scale? If not, why? Bernath Bence, Netherlands
Chris Morris writes:
The trouble with carbon capture and storage (CCS) is that the technology that does exist, won't be rolled out fast enough to make any significant difference this decade, when greenhouse gas emissions need to fall significantly.
The UK for example has allocated £1bn to a CCS infrastructure fund, with the ambition of capturing the equivalent of 10 metric tonnes of carbon dioxide by 2030. To put that in perspective, the UK is estimated to have produced the net equivalent of more than 450m metric tonnes of CO2 in 2019.
Government investment varies hugely around the world. Countries like Saudi Arabia and Australia are relying very heavily on CCS to allow them to continue producing fossil fuels for the foreseeable future, but that means scaling up the technology in a way which has not yet been proven to work effectively.
How do agricultural products like rice and sugar contribute to the increase of CO2? What can we do to help reduce emissions? Ng Wee Meng, Singapore
Chris Morris writes:
Most forms of agriculture produce CO2 emissions in one way or another.
Beef is widely agreed to be the most carbon-intensive food to produce globally, but there are emissions from sugar and rice - these are connected with factors such as deforestation, animal feed, energy used in processing and transport, and packaging.
One study estimates that rice, for example, produces the equivalent of 4kg of CO2 emissions for every 1kg of rice produced. Given that 755 million tonnes of rice are produced every year around the world, that is a lot of CO2. On the other hand, rice is an essential staple food feeding billions around the world.
The best way to help reduce emissions is to try to ensure you eat food which is produced as sustainably as possible - although many people may not have the luxury of that choice.
Would enforcing quotas for meat consumption and flight travels be efficient and feasible? Anonymous, Geneva
Chris Morris writes:
Meat eating (especially beef) and travelling by air both have a sizeable environmental impact.
Eating one or two hamburgers a week for a year creates the same amount of greenhouse gases as heating a UK home for 95 days.
And a return economy flight from London to New York emits about 0.67 tonnes of CO2. That's 11% of the average annual emissions for someone in the UK.
In theory, enforced quotas for meat consumption or flying would make a difference, but there's little political appetite or support for that to happen. Instead, the focus is on encouraging behavioural change.
The UK Climate Change Committee - which advises the government - has recommended that people should consume 20% less meat and dairy by 2030, and 35% less by 2050. People are also being urged to think about flying less.
Using taxation to make certain things more expensive would probably be a more realistic solution than trying to enforce quotas.
Why can't we have an international fund to help poorer countries attain zero carbon emissions? Robert Patterson, Darlington
Chris Morris writes:
That is partly what the current debate on climate finance is all about.
In 2009, rich countries said they would provide $100bn (£73bn) every year to the developing world by 2020. But they have been unable to live up to their promise, and they are now suggesting they will only meet that target in 2023.
Poorer countries need this money to help tackle the effects of climate change that they are already facing. But they also need it to make sure their economies become greener as they develop, on a path to net zero carbon emissions.
If it is people causing climate change, what is being done to stop over-population ? Gaye Schmidt, Perth, Australia
Chris Morris writes:
Overpopulation isn't the root cause of climate change. Rather, it's the excessive emission of greenhouse gases that are heating the planet up. And the richest one per cent of the world's population is responsible for more carbon emissions than the poorest fifty per cent.
It is true to say the population of the planet can't keep increasing indefinitely, because there is a finite number of resources available. But excessive consumption has played a larger role in climate change than a growing global population.
What is the impact of the quantity of methane on climate change? Maya Yossifova, Vienna, Austria
Matt McGrath writes:
Methane is a greenhouse gas, which is released from both natural sources, such as wetlands and termites, and also through human activities such as agriculture, fossil fuel exploitation and landfill sites.
It's a compound of carbon and hydrogen, and this makes it exceptionally good at trapping heat - and a major cause of climate change.
According to the World Meteorological Organisation, methane levels in the atmosphere reached 1,889 parts per billion in 2021.
Concentrations of CO2 are roughly 200 times higher, but methane is calculated to be more than 80 times more potent at warming over a 20-year period.
A United Nations report earlier this year said that efforts to reduce methane emissions should be focused on reducing emissions from landfill sites and gas wells, cutting down food waste and loss, improving livestock management, and encouraging consumers to adopt diets with a lower meat and dairy content.
Are there any positive effects of climate change? Mike Bell, Germany
Matt McGrath writes:
There may well be some short-lived positive impacts to warming, but climate scientists have been quick to shoot them down because they are overwhelmingly outweighed by the negatives.
The most widely quoted "benefit" is the idea that a world with higher carbon levels will see plants grow faster and bigger. This is called the CO2 fertilisation effect.
However, research published last year suggested that this effect is already waning and any idea that it could somehow limit future warming is not supported by the evidence.
What confidence can we have of the impact of COP26 when the world couldn't even come together for an equitable distribution of vaccines? Mahesh Nalli, London
Matt McGrath writes:
There are parallels between the pandemic and the climate crisis, but some key differences as well.
As we've seen over the past 18 months, countries can keep Covid at bay by severely restricting the movements of people across their borders.
Such an approach doesn't work well with rising temperatures that are causing impacts for rich and poor nations alike.
While the question of vaccine inequity is likely to be solved by time and money, the climate crisis requires the rethinking and re-engineering of almost every aspect of our lives, from energy to food to clothing.
Ultimately the vaccine question is a short-term crisis, while climate change is slow moving and multi-dimensional.
Humans are reasonably good at sorting out one, but not so good with the other.
The COP26 global climate summit in Glasgow in November is seen as crucial if climate change is to be brought under control. Almost 200 countries are being asked for their plans to cut emissions, and it could lead to major changes to our everyday lives.
Is the global capitalist model not at odds with climate change and the need for a greener way of life? Andrew, Exeter
Matt McGrath writes:
According to some experts, such as the economist Lord Stern, climate change can be seen as the great failure of the market.
This is because businesses have not generally had to pay for the damage they have caused to the environment.
Global efforts to tackle climate change over the past two decades have focused more on harnessing capitalism to limit warming - for instance, putting a price on carbon and making the polluter pay, to ensure that emissions are ultimately restricted.
Meanwhile, it's also the case that if there's consumer demand for greener products and services, capitalism will try to meet that demand.
But there's evidently still a lot of work to be done to make these approaches work.
Does COP26 really need 25,000 people there? They will generate a lot of CO2, so why can't many elements be online? David, Birmingham
Matt McGrath writes:
The pandemic might be seen as the perfect moment for the UN to use technology for negotiations, and it was attempted during a preparatory meeting for COP in June, which ran for three weeks.
Unfortunately, it didn't go well - time-zone and technology challenges made it almost impossible for countries with limited resources, progress was limited and decisions were put off.
As a result, many developing nations have insisted on having an in-person COP. They feel that it is far easier for their voices to be ignored on a dodgy Zoom connection.
They also bring a lived experience of climate change that it is critical for rich countries to hear first-hand.
There's some evidence that this works. In 2015, the presence of island states and vulnerable nations was key to securing the commitment to limit temperature changes to 1.5C in the Paris Agreement.
What questions do you have about changes in our climate?
In some cases your question will be published, displaying your name, age and location as you provide it, unless you state otherwise. Your contact details will never be published. Please ensure you have read our terms & conditions and privacy policy.
Use this form to ask your question:
If you are reading this page and can't see the form you will need to visit the mobile version of the BBC website to submit your question or send them via email to YourQuestions@bbc.co.uk. Please include your name, age and location with any question you send in.
