PARIS, Feb. 2 (Xinhua) -- Human activities are heating the earth which would bring more disasters to human beings, warned a report of the United Nations climate panel on Friday.

    It was very "likely" or a probability of more than 90 percent that human activities led by burning fossil fuels had facilitated the warming in the past half century, said the final text of the report issued by the Intergovernmental Panel on Climate Change (IPCC), world's most authoritative group on the study of global warming.

    "Global atmosphere concentrations of carbon dioxide, methane and nitrous oxide have increased markedly as a result of human activities" and now far exceed pre-industrial values determined from ice cores spanning many thousands of years, said the report.

    "The global increases in carbon dioxide concentration are due primarily to fossil fuel use and land-use change, while those of methane and nitrous oxide are primarily due to agriculture," it said.

    The final text of the report, approved after overnight talks, is written in a much tougher tone than 2001's report in which the IPCC said the link was "likely" or a probability of 66 percent.

    "Most of the observed increase in globally averaged temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations," said the report, a 21-page summary of scientific findings.

    The accelerating global warming would result in more severe rains, melting glaciers, droughts, heat waves and rising sea levels, warned the IPCC, which groups some 2,500 scientists from over 130 counties.

    The sea ice of Arctic is "more likely than not" to melt in summers by 2100, warned the report.

    World's temperatures would go up by 1.8-4 Celsius degrees in the 21st century, predicted the IPCC, noting that temperature rose 0.7 degrees in the 20th century.

    The group also said sea levels would witness a rise of 18-59 centimeters in the 21st century.

    The report, together with three others, will add pressure on governments to take more effective measures to combat the climate change.

    "We are in a sense (of) doing things that have not happened in 650,000 years based on the scientific evidence," IPCC head Rajendra Pachauri told a press conference.