By Lara Keay, news reporter
Leaders from around the world have come together in Glasgow to take part in COP26.
With representatives from almost every nation on Earth, the UN climate conference is the largest of its kind, bringing hopes of more net zero commitments and global action on climate change.
But the UN's recent annual emissions report made for "bleak" reading, with experts revealing we are "nowhere near where science says we should be".
Scientists say the world is facing minimum global warming of 2.7C by the end of this century 鈥� far beyond the target of 1.5C enshrined by the Paris Agreement in 2015.
So is it too late for COP26 to make a difference 鈥� and do we have too colossal a task ahead of us?
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How fast is the world warming?
This year the term "global heating" was added to the Oxford English Dictionary in response to expert concerns that "global warming" does not reflect the severity of the current climate crisis.
Its definition reads: "Often used in preference to global warming to convey more emphatically the seriousness of climate change caused by human activity and the urgent need to address it."
Each country represented at COP26 has its own action plan for climate change, which the UN refers to as a Nationally Determined Contribution (NDC).
But last week's United Nations Environment Programme (UNEP) annual emissions report said these are "seriously inadequate" at limiting global warming to between 1.5C and 2C by 2100.
It warned that current NDCs would lead to a temperature increase of "at least 3C by the end of the century".
By 2030, they would also only reduce emissions by 7.5%, when 55% is needed to meet the Paris target of 1.5C.
NDCs, however, are separate from net zero commitments (countries promising to becoming carbon neutral) which could reduce potential warming of 2.7C to 3C to between 2.2C and 2.5C.
But according to the report, this would only be possible if NDCs are "made robust and if 2030 promises are made consistent with net zero commitments".
Has COVID lowered our carbon footprint?
As the coronavirus pandemic saw daily life grind to a halt at the start of 2020, carbon dioxide emissions fell.
Researchers estimate that lockdowns across the world caused global emissions to fall by 5.4%.
This was mainly driven by the aviation sector, which saw its fossil fuel emissions fall by 48% on 2019.
Although COVID's impact on the global carbon footprint 鈥� which was double the size of Japan's annual one 鈥� was significant, experts predicted it would be greater, given the global scale of the crisis.
With the UK and other major economies in recovery and restrictions largely lifted, the UN warns: "The COVID-19 crisis offers only a short-term reduction in global emissions and will not contribute to emissions reductions by 2030 unless countries pursue an economic recovery that incorporates strong decarbonisation."
As a "people's advocate" for COP26, Sir David Attenborough claimed earlier this year that climate change will present a much bigger challenge than COVID in the next five to 10 years if leaders do not commit to more action.
Prime Minister Boris Johnson has repeated calls to "build back better" after the pandemic, which includes a green economic recovery.
Living through a global crisis has seen many other countries promise to do the same, with the UN describing recent net zero commitments as "the most significant and encouraging development in 2020".
But experts warn that they must be backed up by government policy between now and 2030.
"The litmus test of these announcements will be the extent to which they are reflected in near-term policy action and in significantly more ambitious NDCs," the emissions report says.
Which countries are pledging to act?
Of the 197 countries represented at COP, 126 have formally adopted, announced or are considering net-zero goals.
They account for 51% of global greenhouse gas emissions.
Former president Donald Trump famously pulled the US out of the Paris Agreement, claiming it was unfair that countries such as India and China were allowed to use fossil fuels, while the United States was expected to decarbonise.
After Joe Biden was elected, in February the US re-joined Paris, with the administration planning to adopt a 2050 net carbon target as part of its climate plan.
If this materialises, the share of global emissions covered by net zero goals would increase to 63%.
Only half of the G20 countries 鈥� with the most powerful economies in the world 鈥� have announced net zero goals.
They are:
- UK 鈥� 2050 (enshrined in law)
- France 鈥� 2050 (enshrined in law)
- EU 鈥� 2050
- Japan - 2050
- South Korea - 2050
- Canada - 2050
- South Africa - 2050
- Argentina - 2050
- Mexico - 2050
- China 鈥� 2060
China and Russia 鈥� the two largest countries in the world 鈥� both trail behind other major economies by only promising carbon neutrality by 2060.
President Vladimir Putin is not coming to Glasgow, but in a phone call ahead of the conference, Boris Johnson urged him to bring Russia's commitment forward by 10 years 鈥� in line with the UK.
The Maldives and Uruguay have the most ambitious net zero targets 鈥� both hoping to achieve them by the year 2030.
But being such a small country, the former lacks policies to get there and will only be able to do so with significant financial support.
Uruguay has managed to defy trends by increasing forest cover at a time of increasing deforestation across South America, which along with other green policies has allowed it to bring forward its net zero projection.
Austria and Iceland also have more ambitious goals 鈥� both with targets of 2040.
Can we afford to take on climate change?
The third pillar of COP26 is "mobilising finance".
In order to limit warming and get to net zero by 2050, the public and private sectors need to make radical financial changes.
COP leaders warn that "every company, financial firm, bank, insurer and investor" needs to contribute to fighting the climate crisis.
They call on fellow governments to fund sustainable infrastructure and promote a greener economy, as well as asking private financial institutions to fund eco technology and innovation.
In 2009, developed countries pledged to mobilise $100bn (拢72.5bn) in climate finance every year by 2020.
As part of the Paris Agreement six years later, they agreed to extend their goal through to 2025.
But Organisation for Economic Co-operation and Development (OECD) figures show that this number was only $78.9bn (拢57.2bn) in 2018.
Experts warn that figures for 2020, 2021 and 2022 are "likely to fall short" as well.
Ahead of the conference in Glasgow, the UK published its Climate Finance Delivery Plan setting out how it will support net zero goals financially up to 2025.
The plan features 拢11.6bn ($16bn) for developing countries over the next five years, including 拢3bn on "nature-based solutions".
But the government has faced criticism by continuing its cut to foreign aid spending 鈥� by 0.5% of national income - until 2024-25, with opposition leaders claiming it is not in line with the $100bn pledge.
Chancellor Rishi Sunak also reduced taxes on fuel and domestic air travel in his budget last week, which many environmentalists have described as hypocritical on the eve of COP.
This week Sky News revealed one UK-funded overseas climate project was assessed against the wrong global warming target.
The emissions for a liquefied natural gas project organised by oil company Total and funded through $1.15bn of UK cash was measured against 2C heating 鈥� not the 1.5C agreed in Paris.
But in Glasgow, former Bank of England governor Mark Carney is hoping to remedy this by expanding his Glasgow Financial Alliance for Net Zero (GFANZ) to get more of the world's financial institutions moving towards carbon neutrality.
Currently 160 firms, worth $70tn (拢50.75tn) are signed up.
What are people willing to do?
According to UN experts, around two thirds of global emissions are linked to "private household activities".
The day-to-day things that produce the most greenhouse gases are travel, powering our homes and the food we eat, which each contribute roughly 20% to lifestyle emissions.
For example, giving up one long-haul return flight can reduce your annual personal emissions by an average of 1.9 tCO2e (equivalent tonnes of carbon dioxide) per capita.
Using renewable energy to power your home could see a 1.5 tCO2e fall and adopting a vegetarian diet a 0.5tCO2e one.
But a Sky News poll earlier this year suggested that over a fifth (23%) of people would not be prepared to make even one key change in their activities to fight climate change.
Almost seven in 10 (69%) respondents said they did not feel personally impacted by it.
But the same amount acknowledged that the crisis is being felt elsewhere in the world.
Only a fifth said they would be willing to see substantial increases in the price of overseas travel, 13% would accept higher meat and animal product costs, and just 2% a hike in heating bills.
Although the UK government has banned the sale of new petrol and diesel cars by 2030, only a third (29%) said they would be willing to give them up.
Will it all be enough?
Although some of the poorest countries in the world are already experiencing the devastating consequences of climate change, the richest are the ones causing it.
Emissions from the wealthiest 1% of the global population account for more than twice the poorest 50%, according to the UN.
In the last 10 years, the four biggest polluters 鈥� China, the US, EU, UK and India 鈥� have made up 55% of global greenhouse gas emissions.
The G20 accounted for 78%.
In order to comply with the terms of the Paris Agreement and limit warming to 1.5C, the richest 1% must reduce their current annual emissions by a factor of at least 30, the UN emissions report says.
It also warns that many of the countries represented in Glasgow have net zero pledges that are too "vague" and are not backed up by concrete policies and their NDCs for 2030.
"Two steps are urgently required," the report says.
"First, more countries need to develop long-term strategies consistent with the Paris Agreement, and second, new and updated NDCs need to become consistent with net-zero emissions goals."
If this doesn't happen, and warming continues at its current rate, it will result in more fatal weather events 鈥� such as flooding, forest fires and tornadoes 鈥� an endangered food and water supply, the melting of most glaciers and the destruction of the coral reef.
Piers Forster, a climate change professor at Leeds University, describes UN warnings on the emissions gap as an "overly bleak picture".
But he says that while we鈥檙e falling short for 2030, longer-term plans could bring us closer in line by the end of the 2000s.
"If you look at their numbers, it shows that the gap in longer term emission targets is almost closed.
"These national plans show that the costs of action are far less than the cost of inaction, so we have it all to play for at [COP26] to close these gaps even further."
Some experts note that UN emission gap projections are "pessimistic" as they don鈥檛 take account of carbon cuts that are already happening 鈥� or pledges made outside of national governments.
Meanwhile, Caterina Brandmayr, head of climate policy at Green Alliance, stresses the importance of "concrete actions, particularly by G7 countries" in Glasgow.
"COP26 must provide a clear route forward to accelerate emission reductions and ensure countries continue to ramp up their near-term climate action," she adds.
Friends of the Earth has a similar view, admitting that while "previous climate talks have been frustratingly slow, they're one of the only spaces where countries in the Global South can participate on an equal footing with industrialised countries like the US, UK and Japan".
They say that if poorer countries already fighting climate change can make their voices heard by the G20 鈥� COP26 has real potential for change.