CANBERRA: Tens of thousands of protesters gathered Friday at rallies around Australia as a day of worldwide demonstrations calling for action to guard against climate change began ahead a UN summit in New York. Some of the first rallies in what is being billed as a 'global climate strike' kicked off in Australia's largest city, Sydney, and the national capital, Canberra. Australian demonstrators called for their nation, which is the world's largest exporter of coal and liquid natural gas, to take more drastic action to reduce greenhouse gas emissions. The Global Strike 4 Climate said protests were staged in 110 towns and cities across Australia on Friday, with organizers demanding government and business commit to a target of net zero carbon emissions by 2030. Similar rallies were planned Friday in cities around the globe. In the United States more than 800 events were planned Friday, while in Germany more than 400 rallies were expected. A similar coordinated protest in March that drew crowds around the world. The protests are partly inspired by the activism of Swedish teenager Greta Thunberg, who has staged weekly demonstrations under the heading 'Fridays for Future' over the past year, calling on world leaders to step up their efforts against climate change. Many who have followed her lead are students, but the movement has since spread to civil society groups. Australian universities have said they will not penalize students for attending Friday's rallies, while Australian schools vary on what action, if any, they take against children who skip classes to attend demonstrations. Siobhan Sutton, a 15-year-old student at Perth Modern School, said she would fail a math exam by attending a protest in the west coast city of Perth. 'I have basically been told that because it is not a valid reason to be missing school — it is not a medical reason or anything — I am going to get a zero on the test if I don't actually sit it,' she said. 'Even though we ourselves aren't sick, the planet which we live on is, and we are protesting and fighting for it,' she added. Siobhan said her math teacher had given her the option to sit the exam before Friday, but she was unable to do so because of her commitments as one of the protest organizers. Acting Prime Minister Michael McCormack said students should be in school. 'These sorts of rallies should be held on a weekend where it doesn't actually disrupt business, it doesn't disrupt schools, it doesn't disrupt universities,' McCormack told reporters in Melbourne. 'I think it is just a disruption,' he added. The demonstrations come as Australia's centre-left opposition mulls abandoning its policy, rejected at May elections, of reducing Australia's greenhouse gas emissions by 45% below 2005 levels by 2030. Prime Minister Scott Morrison's conservative coalition won a surprise third term with a commitment to reduce emissions by a more modest 26% to 28% in the same time frame. Morrison is in the US for a state dinner with President Donald Trump on Friday and has been criticized for failing to include in his New York itinerary the UN climate summit on Monday, when leaders will present their long-term plans for curbing greenhouse gas emissions. Government lawmaker Craig Kelly on Thursday told students who planned to join Friday's climate strike that 'you are being used and manipulated and everything you are told is a lie.' 'The facts are, there is no link between climate change and drought; polar bears are increasing in number,' Kelly told Parliament. 'Today's generation is safer from extreme weather than at any time in human history,' he added. Some companies are encouraging their employees to join the climate strike. Australian Council of Trade Unions, which represents labour unions, said it supported employees taking time off work to protest. The council said in a statement that it 'must take a stand for our future when our government will not.'