By MICHELE F. MIHALJEVICH

Indiana Correspondent

FORT WAYNE, Ind. — Earth’s global surface temperature is on track to increase by 1.5 degrees Celsius (2.7 degrees Fahrenheit) over pre-industrial levels in the next few decades – a situation that could cause dire consequences, warns a recent United Nations report.

The Intergovernmental Panel on Climate Change (IPCC) said human-induced warming has already increased about 1 degree Celsius from pre-industrial levels. If the current warming rate continues, the world would reach human-induced global warming of 1.5 degrees Celsius by 2030-52, the panel said. The IPCC report was released Oct. 8.

“One of the key messages that comes out very strongly from this report is that we are already seeing the consequences of 1 degree Celsius global warming through more extreme weather, rising sea levels and diminishing Arctic sea ice, among other changes,” explained Panmao Zhai, co-chair of IPCC Working Group 1.

The Trump administration, meanwhile, believes the global mean surface temperature could increase by about 3.48 degrees Celsius (6.27 degrees Fahrenheit) by 2100, according to the National Highway Traffic Safety Administration.

The information was included in a Draft Environmental Impact Statement regarding President Donald Trump’s plan to freeze federal gas mileage standards for cars and light trucks built after 2020. The report was released in July.

The Paris Agreement on climate change adopted by 195 nations in 2015 called for holding “the increase in the global average temperature to well below 2 degrees Celsius above pre-industrial levels, and pursuing efforts to limit the temperature increase to 1.5 degrees Celsius above pre-industrial levels.”

Global warming could cause heavy precipitation in some regions and droughts in others, the report said. Species loss and extinction are also possible, as is a reduction in projected food availability in some areas.

To achieve the goal of a 1.5 degrees Celsius increase limit, global net human-caused carbon dioxide (CO2) emissions would need to drop about 45 percent from 2010 levels by 2030, and reach net zero by 2050, the panel said.

The report recommends a greater reliance on renewable energy such as solar and wind. It also suggests finding technologies to remove CO2 from the atmosphere. The report cautioned such techniques are unproven at large scale and some may carry significant risks for sustainable development.

As for agriculture, the panel said increased temperatures could impact the production of cereals such as wheat, maize and rice. Production losses could be lowered if varieties better suited to changing climate conditions are adapted.

Conservation agriculture, improved livestock management, increasing irrigation efficiency and management of food loss and waste are some steps recommended by the panel.

The report doesn’t contain a lot of new information, said Brent Sohngen, a professor of environmental and resource economics at The Ohio State University.

“Nothing has really changed in terms of the science, especially in terms of agriculture,” he explained. “We don’t have any evidence the impacts of climate change are going to happen any sooner for agriculture. Eventually, crop yields will start to fall relative to what they should be (as temperatures increase). Farmers are going to have to adapt – change management practices or maybe plant different crops.”

Sohngen said he’s in favor of stronger carbon mitigation polices but noted they’re costly. Countries probably won’t want to spend enormous amounts of money on something other countries might not spend on, he added.

“I think the scientists are pretty straight on (with the conclusions found in the report),” Sohngen said. “I think those impacts are potentially real. I have no doubt the outcomes are possible.”

Drew Lerner, president of World Weather, Inc., said the panel started with a conclusion and then tried to prove that conclusion. “We do have to stop polluting our atmosphere, but we have to resist being too alarming,” he opined.

Climate change is largely a perception, Lerner said, because as people get older, the weather has deviated from what they remember as children. “The perception is the world’s weather is changing, that it’s becoming more extreme,” he said.

“We’re looking through a very narrow window of time. There was probably very volatile weather in the past. We didn’t have the data then we have today. We as scientists are trying our very best to assess changes that have occurred since childhood.

“We are polluting our atmosphere. Particulate matter, along with some aerosols, acts in a manner to hold in heat. The greenhouse matter is a real one,” he said.

Sunspot activity, which occurs in cycles lasting on average about 11 years, could also impact the world’s weather, Lerner noted. “We’re in solar minimum now,” he said. “Some believe that will put us in a colder situation. Solar minimum is a part of the debate. What we know factually is we continue to pollute the atmosphere.

“It’s still quite warm in the oceans and the tendency is for temperatures to be at a warmer bias. Expect more volatility and more extremes. The next 10 to 20 years, we’re going to see some wild weather until the atmosphere settles down. The volatility is going to stay with us whether we understand the cause or not.”