How accurate were the predictions about climate change made 20 years ago

In 2000, experts made predictions about climate change on the planet who, in their opinion, was supposed to happen in 20 years. Were these predictions accurate? To understand offers USA Today.

Насколько точными были прогнозы об изменениях климата, сделанные 20 лет назад

Photo: Depositphotosclima

“Now that the predictive model correctly told us 20 years ago: if we continued to add to the atmosphere fossil fuel with increasing speed, we would see more and more wide range of consequences, including lower rates of Arctic sea ice, sea level rise and changes in precipitation patterns,” said Weather Underground meteorologist Robert Henson.

Overall, we are close to the forecasts made in 2000 regarding carbon dioxide concentration, global temperature and sea level, said Hanson. Look at the predicted indicators of climate change for 2020:

Carbon dioxide

Carbon dioxide is a greenhouse gas that, according to scientists most responsible for global warming. According to the National oceanic and atmospheric administration, from the beginning of 90-ies the level of carbon dioxide in the Earth’s atmosphere has increased from 358 ppm to almost 412 parts per million. 15% more for 27 years.

The rise in sea level

Since 1992, global sea level is rising at an average rate of 2.9 millimeters per year. All is 78.3 mm, according to NOAA.

A meteorologist at Pennsylvania State University, Michael Mann argued that we had underestimated the speed of the collapse of the ice cover that has “consequences for future sea-level rise”.

Both the giant ice sheet in the world has lost a huge amount of ice over the last two to three decades: according to a study published by the National Academy of Sciences, the Greenland ice sheet has lost 5.2 trillion tons of ice from 1993 to 2018.

According to a study in the journal Nature, in the period from 1992 to 2017 Antarctic ice sheet lost 3 trillion tons of ice.

Weather disasters

Mann said that we “underestimated the sharp increase in extreme weather events, such as the unprecedented heat, drought, forest fires and floods we have witnessed in recent years.”

Since 1993 occurred 212 natural disasters, which cost the United States at least $ 1 billion each, taking into account inflation.

In total they cost 1.45 trillion dollars and killed more than 10,000 people. This is an average of 7.8 such disasters per year since 1993, compared to 3.2 per year between 1980 and 1992, according to NOAA.

“Just as climate models almost certainly underestimate the impact of climate change on these extreme weather conditions, the predictions of these models are also likely to underestimate future increases in such phenomena,” wrote Mann in the past year.

“In General, our models understand this plus-minus right,” said Zeke Hausfather, a scientist from the University of California at Berkeley.

Global growth

Hanson noted that global climate models were on the right path 20 years ago, global temperatures will continue to rise as greenhouse gases continue to accumulate in the atmosphere. This was confirmed: according to NOAA, the average temperature of the planet has increased by slightly more than degree Fahrenheit since the mid 90-ies.

According to Hanson, these climate models were not designed to predict variability from decade to decade, so we are not fully anticipated the slowdown in global warming of the atmosphere in the first decade of this century, and much faster growth in the 2010-ies, which was associated with an increasing rate of accumulation of heat in the ocean.

According to the National data center for snow and ice, annual mean sea-ice extent in the Arctic declined from 4.7 million square miles in 1992 to 3.9 million square miles in 2019. This is 17% less.

Drought and forest fires

“Beyond the prospects for 2000 also came out some aspects of regional climate change,’ said Henson. For example, it is now clear that droughts in California are likely to be “hot”, and it laid the Foundation for a more prolonged and devastating seasons of forest fires”.

According to the National interagency fire center, the number of acres burned in forest fires in the USA has increased by more than half from five-year average of 3.3 million acres in 1990, to 7.6 million acres in 2018.

“Flood Sunny day”

“The threat posed by “flood Sunny day”, much more than in 2000, said Henson. — Tidal flooding is much more common in many parts of the Gulf of Mexico and the Atlantic ocean than it did 20 years ago, and NOAA predicts that some areas may experience more than 80 days of flooding a year by 2040 years.”