London, 1 November 2021 (PA Media/dpa/MIA) - The international community's latest bid to combat catastrophic climate change got under way on Monday in the Scottish city of Glasgow. The host of the UN Climate Change Conference (COP26), British Prime Minister Boris Johnson, mapped out high hopes for the summit in his opening address, while his Barbadian counterpart implored fellow leaders in a blistering speech to "try harder." "If summits alone solve climate change then we wouldn't have needed 25 previous COP summits to get where we are today," Johnson said. "But while COP26 will not be the end of climate change, it can and it must mark the beginning of the end." He added: "In the years since Paris, the world has slowly and with great effort and pain built a lifeboat for humanity and now is the time to give that lifeboat a mighty shove into the water like some great liner rolling down the slipways of the Clyde." At the invitation of the United Nations, government representatives from around 200 countries plan to spend a fortnight in Glasgow discussing how humanity can contain accelerating global warming. More than 28,000 delegates, observers and journalists are expected at the event. In the 2015 Paris Agreement, world leaders committed to capping warming to well below 2 degrees Celsius and pursuing efforts to limit it to 1.5 degrees, compared to pre-industrialization-era levels. However, hopes for ambitious and decisive action at the Glasgow summit were dampened by the G20 talks in Italy on Sunday, in which leaders of the world's largest economies failed to agree on target dates for achieving carbon neutrality or ending coal-fuelled power. Johnson warned of the dangers of rising temperatures as he opened COP26: "Four degrees and we say goodbye to whole cities - Miami, Alexandria, Shanghai - all lost beneath the waves." He concluded his speech by saying that the summit must mark the moment when humanity began to "defuse that bomb" of climate change. In her address, Barbadian Prime Minister Mia Mottley appealed to those in attendance to act, while launching a veiled attack on those who chose not to come to Glasgow for the key talks. "We do not want that dreaded death sentence and we've come here today to say 'try harder, try harder.'" UN Secretary General Antonio Guterres also addressed the attendees in Glasgow, including US President Joe Biden, German Chancellor Angela Merkel and Indian Prime Minister Narendra Modi. He said the goal of 1.5 degrees Celsius must be kept alive and called for solidarity with developing countries. The world's "addiction to fossil fuels is pushing humanity to the brink," Guterres added. "We face a stark choice: either we stop it - or it stops us. "It's time to say: enough. Enough of brutalizing biodiversity. Enough of killing ourselves with carbon. Enough of treating nature like a toilet. Enough of burning and drilling and mining our way deeper. We are digging our own graves." Chinese President Xi Jinping, Russian President Vladimir Putin, Brazilian President Jair Bolsonaro and Turkish President Recep Tayyip Erdogan are among those who have chosen not to attend the conference in person.