Page 28 - ARUBA TODAY

A28 SCIENCE
Tuesday 30 May 2017

What if U.S. quits climate deal? Doesn’t look good for Earth

BY SETH BORENSTEIN whelmingly agreed that al emissions and pledges,
AP Science Writer the warming the planet is simulated global emissions
WASHINGTON (AP) — Earth undergoing now would be if every country but the U.S.
is likely to reach more dan- faster and more intense. reaches their individualized
gerous levels of warming The world without U.S. ef- goals to curb carbon pollu-
even sooner if the U.S. re- forts would have a far more tion. Then they calculated
treats from its pledge to cut difficult time avoiding a what that would mean in
carbon dioxide pollution, dangerous threshold: keep- global temperature, sea
scientists said. That’s be- ing the planet from warm- level rise and ocean acidi-
cause America contributes ing more than 2 degrees fication using scientifically-
so much to rising tempera- Celsius (3.6 degrees Fahr- accepted computer mod-
tures. enheit) above pre-industri- els.
President Donald Trump, al levels. By 2030, it would mean an
who once proclaimed So the efforts are really extra 3 billion tons of car-
global warming a Chinese about preventing another bon dioxide in the air a
hoax, said in a tweet Satur- In this Jan. 20, 2015 file photo, a plume of steam billows from the 1.6 degrees Fahrenheit (0.9 year, according to the Cli-
day that he would make his coal-fired Merrimack Station in Bow, N.H. degrees Celsius) from now. mate Interactive models,
“final decision” this coming “Developed nations — and by the end of the cen-
week on whether the Unit- special computer model add as much as half a de- particularly the U.S. and tury 0.3 degrees Celsius of
ed States stays in or leaves scenario designed to cal- gree of warming (0.3 de- Europe — are responsible warming.
the 2015 Paris climate culate potential effects. grees Celsius) to the globe for the lion’s share of past “The U.S. matters a great
change accord in which Scientists said it would wors- by the end of century. emissions, with China now deal,” said Climate Inter-
nearly every nation agreed en an already bad prob- Scientists are split on how playing a major role,” said active co-director Andrew
to curb its greenhouse gas lem and make it far more reasonable and likely that Rutgers University climate Jones. “That amount could
emissions. difficult to prevent crossing scenario is. scientist Jennifer Francis. make the difference be-
Leaders of seven wealthy a dangerous global tem- Many said because of “This means Americans tween meeting the Paris
democracies, at a summit perature threshold. cheap natural gas that have caused a large frac- limit of two degrees and
in Sicily, urged Trump to Calculations suggest it displaces coal and grow- tion of the warming.” missing it.”
commit his administration could result in emissions of ing adoption of renewable Even with the U.S. doing Climate Action Tracker, a
to the agreement, but said up to 3 billion tons of addi- energy sources, it is unlikely what it promised under the competing computer sim-
in their closing statement tional carbon dioxide in the that the U.S. would stop Paris agreement, the world
that the U.S., for now, “is air a year. When it adds up reducing its carbon pollu- is likely to pass that 2 de- ulation team, put the ef-
not in a position to join the year after year, scientists tion even if it abandoned gree mark, many scientists fect of the U.S. pulling out
consensus.” said that is enough to melt the accord, so the effect said. somewhere between 0.1 to
“I hope they decide in ice sheets faster, raise seas would likely be smaller. But the fractions of addi- 0.2 degrees Celsius (0.18 to
the right way,” said Italy’s higher and trigger more ex- Others say it could be tional degrees that the U.S. 0.36 Fahrenheit) by 2100. It
prime minister, Paolo Gen- treme weather. worse because other coun- would contribute could uses a scenario where U.S.
tiloni. More downbeat was “If we lag, the noose tight- tries might follow a U.S. exit, mean passing the thresh- emissions flatten through
German Chancellor An- ens,” said Princeton Uni- leading to more emissions old faster, which could in the century, while Climate
gela Merkel, who said the versity climate scientist Mi- from both the U.S. and the turn mean “ecosystems be- Interactive has them rising.
leaders’ talks were “very chael Oppenheimer, co- rest. ing out of whack with the One of the few scientists
difficult, if not to say, very editor of the peer-reviewed Another computer simula- climate, trouble farming who plays down the harm
unsatisfactory.” journal Climatic Change. tion team put the effect of current crops and increas- of the U.S. possibly leav-
In an attempt to under- One expert group ran a the U.S. pulling out some- ing shortages of food and ing the agreement is John
stand what could happen worst-case computer simu- where between 0.1 to 0.2 water,” said the National Schellnhuber, the director
to the planet if the U.S. pulls lation of what would hap- degrees Celsius (0.18 to Center for Atmospheric Re- of the Potsdam Institute for
out of Paris, The Associated pen if the U.S. does not curb 0.36 degrees Fahrenheit). search’s Kevin Trenberth. Climate Impact Research
Press consulted with more emissions, but other nations While scientists may dis- Climate Interactive, a team and the scientist credited
than two dozen climate do meet their targets. It agree on the computer of scientists and computer with coming up with the 2
scientists and analyzed a found that America would simulations they over- modelers who track glob- degree goal.q