Some 7,348 major disaster events were recorded globally, claiming 1.23 million lives, affecting 4.2 billion people and causing $2.97 trillion in economic losses during the two-decade period.
A new report from the United Nations Office for Disaster Risk Reduction (UNDRR) says that climate change has nearly doubled the number of major natural disasters that have occurred around the world between 2000-2019 when compared to the previous 20-year period.
Debarati Guha-Sapir of the Centre for Research on the Epidemiology of Disasters at the University of Louvain, Belgium, which provided data for the report, said: "If this level of growth in extreme weather events continues over the next twenty years, the future of mankind looks very bleak indeed".
A jump in climate-related disasters this century, along with the global coronavirus pandemic, show political and business leaders are failing to stop the planet turning into "an uninhabitable hell" for millions, the United Nations said on Monday.
"It is baffling that we willingly and knowingly continue to sow the seeds of our own destruction", said UNDRR chief Mami Mizutori and Debarati Guha-Sapir of Belgium's Center for Research on the Epidemiology of Disasters, in a joint foreword to the report.
Local villagers travel through a flooded street following recent rains in Phnom Penh, Cambodia, on 12 October.
To avoid that happening, the world must act urgently to invest in prevention, climate change adaptation and disaster risk reduction, Mizutori said.
The report did not touch on biological hazards and disease-related disasters like the coronavirus pandemic, which has killed over one million people and infected over 37 million in the past nine months.
"COVID-19 is but the latest proof that political and business leaders are yet to tune into the world around them", she added in a statement.
Drought, floods, earthquakes, tsunamis, wildfires and extreme temperature events caused major damage. The last 20 years have witnessed 6,681 climate-related disasters compared to 3,656 during 1980-1999.
Ms Mizutori said public health authorities and rescue workers were "fighting an uphill battle against an ever-rising tide of extreme weather events".
Although the UNDRR report notes that there has been some success in protecting vulnerable communities from the effects of natural disasters-largely due to improved early warning systems and disaster preparedness and response-the projected rise in global temperatures in coming decades threatens to make these improvements "obsolete in many countries", according to UNDRR.
Monday's report relied on statistics from the Emergency Events Database, which records all disasters that kill 10 or more people, affect 100 or more people or result in a state of emergency declaration. The countries most affected by disaster events during this period were China (577 events), the United States (467 events), and India (321 events). The 2004 Indian Ocean tsunami, which took more than a quarter of a million lives, was the deadliest.
Global temperatures will continue to warm over the next five years, and may even temporarily rise to more than 1.5 degrees Celsius above pre-industrial levels, the World Meteorological Organization (WMO) said in July.