Half a Degree Makes a Big Difference for Global Climate

By Nathaniel Scharping | April 22, 2016 3:28 pm
tractor-drought

(Credit: Johan Larson/Shutterstock)

World leaders meeting Friday at the United Nations headquarters in New York hope to make this Earth Day a historic one.

More than 150 countries are expected to sign the Paris Agreement, an accord reached last December designed to keep global warming “well below” 2 degrees Celsius by the end of the century, with some nations arguing that the world should rally around a more stringent threshold of 1.5 C. And the difference between the two goals might be significant: A new study shows that the world would look substantially different if mean global temperatures rise by 2 C, rather than 1.5 C.

Small Change, Big Impact

In the paper, a team of European researchers used multiple sets of climate models to analyze the difference between a planet that warms 1.5 degrees or 2 degrees by 2100. It’s a fractional difference, but it holds significant ramifications for at-risk areas near the equator, as well as for populations in Third World countries that will be most affected by climate change.

Sea levels would rise by a third of a foot more if the planet warms by 2 C as opposed to 1.5 C, and swelling coastal estuaries would allow the oceans to creep further into coastal cities. Under the 2 C scenario, nearly every reef worldwide would be at a high risk of degradation, compared to the still-unsettling 70 percent under the 1.5 C contingency, according to researchers’ models. They published their work Thursday in the journal Earth System Dynamics.

Third World Nations Hardest Hit

The researchers find that poor countries near the equator have the most riding on a half degree. With another half a degree increase in temperature, Central America and West Africa would see a twofold decrease in crop yields, compounding issues of food production in regions that are among the most affected by hunger and starvation.

Droughts too would grow worse in critical regions as the globe warms, the researchers say, with the Mediterranean at particular risk. Heat waves are also likely to increase in both length and duration in the tropics, affecting both crops and people. Central America, South Africa and Australia also stand to lose under this scenario, with the amount of water available decreasing by 10 percent under a 1.5 C scenario, and 20 percent if we reach the 2 C threshold.

Most of the models researchers looked at predict increases in crop yields and water levels for regions near the poles, where warming temperatures could prove to be a boon for food production. However, these regions tend to be sparsely populated and more developed, meaning that an increase in food production won’t yield much benefit locally. The populations with the most to lose from climate change, on the other hand, tend to live in areas that will be hardest hit.

Big Changes, Small Numbers

This study provides an insightful perspective of the impact an imperceptible temperature difference can have when applied on a global scale.

While half a degree may seem negligible, it’s important to remember that it is a global average. In some “hot spots”, temperatures are likely to increase far more, offset by smaller increases elsewhere. The impact climate change has on humanity rests on where these changes occur.

The 2 C breaking point represents the extreme for the signees of the Paris Agreement, beyond which humanity enters unknown territory. Even well below that number, we still will not be spared from droughts and rising sea levels. The fate of the agreement now rests in the hands of individual countries that are responsible for enacting the measures laid out in Paris.

It is well worth remembering that even small changes can make a big difference.

CATEGORIZED UNDER: Environment, top posts
ADVERTISEMENT
  • polzzlop

    2C global average — Tropical zone would change little.
    Other places would benefit considerably.

  • OWilson

    If you take the entire satellite record which covers almost 37 years, including this current El Nino, it is up 0.73 degrees.

    Assume the increasing rate remains steady over the next 84 years, with no “pause” or “hiatus”, then the Earth will attain an increase in temperature of 1.67 degree by 2100.

    That’s less than the U.N. Stated goal, and far less than the dire “solutions” promise to deliver.

    All the rest is propaganda!

    (You can all go home now and throw away the meds :)

  • http://www.mazepath.com/uncleal/qz4.htm Uncle Al

    If temperature is below historic average (when comparing a 20th century farm thermometer to a 21st century airport thermometer), it is weather. If Santa Ana winds blow through Souther Calfiornia or a haboob through Arizona, it is Klimate Kaos and the Carbon Tax on Everything. Minority Report, 2002 – precrime!!!

    If you want to end sea ocean rise, 1) stop pumping primordial ground water, 2) irrigate Australia, the Sahara Desert, and the American southwest with captured rainwater, and 3)re-beaver North America, then every arid area worldwide.

  • John C

    New York City underwater? Gas over $9 a gallon? A carton of milk costs almost $13? Welcome to June 12, 2015. Or at least that was the wildly-inaccurate version of 2015 predicted by ABC News exactly seven years ago. Appearing on Good Morning America in 2008, Bob Woodruff hyped “Earth 2100”, a special that pushed apocalyptic predictions of the then-futuristic 2015.

    ———-

    We’re doomed by June 2015. The 97% settled science consensus as communicated by the major media say so.

    • OWilson

      They were just parroting the communist propaganda, that Western Capitalism was doomed.

      They still live in hope!

  • Jarrod Carter

    CO2 Kills yo! Except for all the plants that use it to stay alive and create food for all of those animals that eat plants to stay alive.

    • OWilson

      In Today’s news:

      “Rise in CO2 has ‘greened Planet Earth

      Carbon dioxide emissions from industrial society have driven a huge growth in trees and other plants.

      A new study says that if the extra green leaves prompted by rising CO2 levels were laid in a carpet, it would cover twice the continental USA.”

      The new study is published in the journal Nature Climate Change by a team of 32 authors from 24 institutions in eight countries.

      But, as usual, the researches have to be dragged kicking and screaming to the conclusion :)

      The lead author, Prof Ranga Myneni from Boston University, told BBC News the extra tree growth would not compensate for global warming, rising sea levels, melting glaciers, ocean acidification, the loss of Arctic sea ice, and the prediction of more severe tropical storms.”

      (He left out killer bees and killer snakes)

      • Jarrod Carter

        How dare you use science to convince people of the obvious. You sir are…smart!

        • OWilson

          Your fault.

          You got me started :)

          • Jarrod Carter

            A mish mash of all three, I would opine!

          • cgosling

            Artic ice arctic ice is melting rapidly, ask any polar bear. Antarctic ice is created by snowfall which is increasing, but the top ice it forms does not nearly make up for the the loss of foundation ice which is melting at record speed and is causing whole ice shelves to crash into the sea.

          • OWilson

            That wasn’t the subject of the post, but since you mention it, Arctic ice cover is about the same today as it was 10 years ago. – NSIDC

          • wangweilin

            Polar bears don’t talk and the WAIS has volcanic activity under it heating the water.

  • Jim

    In 1996 the mean temp for Earth was 58.7 degrees.
    In 2016 the mean temp for Earth is: 58.7 degrees according to The whimsical right zinger on Facebook… I think rising temps are a fact of life (and nature as we know it) W probably can’t do much about it in the long run, so perhaps we should PREPARE for the changes and make do.

  • bwana

    “Sea levels would rise by a third of a foot more if the planet warms by 2 C as opposed to 1.5 C, and swelling coastal estuaries would allow the oceans to creep further into coastal cities. Under the 2 C scenario, nearly every reef worldwide would be at a high risk of degradation, compared to the still-unsettling 70 percent under the 1.5 C contingency, according to researchers’ models.”

    Well then, I guess people should start moving to higher ground! This isn’t the first time temperatures have increased (or decreased) and sea levels have increased (or decreased), and it won’t be the last time. Get over it! It is simply nature at work; live with it, or die with it!

    • OWilson

      In coastal areas where the very rich Democrats live, Boca Raton, Long Island, Malibu, Miami, Cape Cod, Chappaquik, Martha’s Vineyard, the price of waterfront land is soaring.

      “Why are they so much more knowledgeable than non political scientists?” :)

      • bwana

        They probably aren’t more knowledgeable, they just like the ocean view… But they’ll be the first to ask for government assistance when the Atlantic is lapping at their front door!

        • OWilson

          And when might we expect this latest Doomsday scenario? :)

          Inquiring minds, I mean “Enquirer” minds, need to know :)

          • bwana

            It could be 50 years, or 200 years, or 1,000 years. All depends on mother nature’s rate of warming. We are coming out of an ice age. At some point we’ll have much the same sea levels and coast lines we had after the last ice age (and the one before that, ad nauseam)…

            Some island nations are already seeing the impact of rising sea levels, so it is more than simply someone’s made up story.

          • OWilson

            AGW Chicken Little Alarmists aside, we will do what we have been doing for 300,000 years

            Some will adapt and thrive.

            Others will run over the cliff with the rest of the lemmings.

            It’s just Darwinism in action!

            By the way, let me know when I can get some cheap waterfront in the Saychelles, Maldives, or for that matter, Cape Cod and Malibu. Even, gasp!, Venice. :)

          • bwana

            It is indeed survival of the fittest!

            But I still wouldn’t recommend buying on the waterfront…

          • OWilson

            You obviously know nothing about real estate, where the mantra is “the demand for waterfront property can never keep pace with population, because they just aren’t making any more of it”.

            The models are solid.

            (of course for those heavily subsidized idiots who live below sea level, or on historic flood plane land, well, let’s just say, Darwin and P.T Barnum were right :)

          • bwana

            Your rule applies to ALL real estate, not just waterfront acreage.

          • OWilson

            Then I have some nice wetland in Florida to sell you! :)

          • bwana

            I prefer snow in winter rather than humid, sweaty climates…

          • OWilson

            What’s wrong with jungles? (Oops, I mean Rain Forests :)

          • cgosling

            “Enjoy yourself, it’s later than you think!”

  • okiejoe

    “Heat waves are also likely to increase in both length and duration in the tropics” BOTH length and duration? How about length and severity or some other words that aren’t synonyms.

  • cgosling

    Chances are, those who don’t believe in global warming are republican and conservative. Why is that, will someone explain? Why are they so much more knowlegeable than non political scientists?

    • bwana

      Actually, both houses of the US government have acknowledged global warming is occurring. They just haven’t decided what is causing it?

    • wangweilin

      I’m conservative and believe that global warming is occurring–anybody can look at temperatures since the last ice age and see it’s warmer. As to the current alarm over something that’s happened before and will happen again, I think by looking at the multiple failed predictions from people like Holdren and Hansen you have to conclude the current efforts to create a catastrophic narrative are animated by politics and personal aggrandizement. After all if Gore, et al really believed what they were saying would they have multiple mansions, private aircraft and a high carbon output lifestyle. Recent stories of planet wide greening due to CO2, which by the way is not the major greenhouse gas, are the other side of the coin.Two sides to the story, one political the other factual. Do a historical search of climate doom news from the 1800’s to present and you’ll find the narratives repeating and failing then re-appearing again. The earth has been warmer…the earth has been cooler…it will be warmer again…it will be cooler again…it’s all in the geological record. Maybe the current crop of true believers have a stronger than usual Messiah complex.

      • cgosling

        Dear Mr. Wangweillin. So you believe In climate change but not in its dangerous consequences because climate scientists have been wrong in the past. Stop and think what you have just said. Because scientists make mistakes, we cannot believe them. You have just rejected every bit of scientific discovery in the world. Few scientist ever get a theory right the first time around. A theory usually takes revision and confirmation and time before it is accepted as being correct. But eventually some theories are proven and accepted by most scientists. Climate change is one of those theories like biological evolution that is accepted by 97 percent of scientists from all specialties. I have an open mind and will accept revisions even at this late date. But some discoveries are so pernicious that they require immediate reaction, such as climate change. Why? Because it will require a huge and sustained effort to slow and stop this threat to our fragile world. Most of those who don’t believe in the climate threat we now face because of lack of evidence, believe in a loving , all powerful deity who has no scientific evidence to support his existence. Do you believe in only those things that support your preconceived ideas? I hope not.

        • wangweilin

          Over 95% of the predictive models have been wrong. Geologic history shows wide variations and yet here we are. Would you go to a doctor who was wrong 95% of the time? Facts speak for themselves, historically and currently. Please point out one assertion I made in my post that is factually wrong.

          • cgosling

            Dear Mr. Wangweillin, You apparently don’t understand the scientific method. Over time, science usually has a record of more errors than breakthroughs, that’s the nature of science. Our society is based upon scientific methodology, experimentation and revision. We cannot reject space technology because of past failures. Scientific failure is vital because it keeps us on the right path. We need to compare the mistakes of the past and learn from them.

          • wangweilin

            You didn’t address a single point I made. I’m likely more science and fact oriented than you by education and daily work. Just keep spouting the narrative.

          • OWilson

            “Climate science” is to physics, what Astrology is to astronomy, or what Chiropractic is to medicine. It’s based on belief. There is no application normal scientific rigor whatsoever.

            (Nature (or settled science) doesn’t work in even numbers, 10 years to save the planet. 2 degrees by 2100, 400 ppm tipping points :)

            It can be practiced by opportunistic politicians like Al Gore and Obama, and those at the U.N., or E.U., without regard for qualifications.

            It’s the only “science” that takes failed results, failed models and failed doomsday cool-ade predictions and sells them to the sheep, just like the shamen, seers, oracles, medicine men, rain dancers, snake oil salesmen and fortune tellers have always done :)

            They’ll never run out of customers, as Barnum always said.

            Enemies of Western Culture have been trying to figure a way to end capitalism for ever, without success.

            By shutting down the energy sources that power Western Prosperity, this is the closest they have yet come.

          • cgosling

            Owilson- You claim climate science is based upon belief and there is no scientific vigor applied
            By definition belief is something unsupported by scientific inquiry. Climate science is supported by numerous science specialties which all agree with the now accepted fact that humans have contributed to climate change and the earth, oceans and atmosphere is warming faster than expected. We can joke about buying ocean side property but the undeveloped world faces a real and terrible crisis of displaced people, starvation, war, and disease. Climate change is happening already chicken little, and it will effect us all.

          • OWilson

            LOL, We’re still waiting for those “200 million refugees by 2010” – U.N. :)

            The end is nigh! Give up your worldly goods, and ye shall be saved!

            Second oldest profession!

            You first, Alphonse :)

          • http://oldephartte.blogspot.ca/ opit

            “Climate science is supported by numerous science specialties which all agree with the now accepted fact that humans have contributed to climate change and the earth, oceans and atmosphere is warming faster than expected. ” What then are ‘deniers’ except refutation of the allegation of consensus ?

        • wangweilin

          Without a Google search you can’t even tell me who did the 97% study or its methodology. It has been proven factually wrong and statistically flawed. What about the 10’s thousands of other scientist who disagree. Disagreement is how science moves forward, not consensus.

        • OWilson

          Ahem, it’s about reality, not your particular “beliefs”.

          It’s those failed models. Arctic Ice is above where it was 10 years ago (NSIDC), Antarctic ice is setting records, and more is accumilating overall than is being lkost (NASA)

          The satellite rocord 37 years,(NOAA) says that at the current rate of warming, we will add 1.67 degrees of warming by 2100.

          It’s those failed, “Tipping Points”

          It’s the “failure”, stupid!

          • wangweilin

            Thanks for the backup O. You want to see a liberal dig in and double down just include easily verifiable facts. Liberals don’t give a crap about facts and rarely if at all respond to the content of a post. I do this for fun. It only shows that liberals are mentally ill.

          • http://oldephartte.blogspot.ca/ opit

            If modeling scattered land temperature readings on a water planet was worth doing, modeling would have to work ( it does not ) and would have to tell us something significant about results which are small enough to fall within margins of error for data readings. Satellite data is still new relative to cyclic weather patterns. None of it is data : just mathematical masturbation in a place where daily variation is multiples of the so called scary projections regardless….and none of it is data about future conditions. That cannot exist.

          • wangweilin

            True. I recall making a graph in engineering class lab that showed the ripple on a DC power supply. It was marked as a poor example of a graph since I had only charted the variation and not the full scale of the voltage. Same with temperatures as you note the over 100x multiples in just a day for most places.

      • http://oldephartte.blogspot.ca/ opit

        And maybe your idea that non political scientists are those who agree deserves questioning. Positing prognostication as accepted reality flies in the face of assessing facts. Prophecy is not fact.

        • wangweilin

          Question only the hypothesis. When observed data and hypothesis are in disagreement the observed data is the reference point – that’s science. To promote the hypothesis in the face of conflicting data is politics. Reality has priority over narrative.

          • http://oldephartte.blogspot.ca/ opit

            No argument about that point…except when dealing with activists who do not find acknowledging reality convenient.

    • http://oldephartte.blogspot.ca/ opit

      Why would I try to explain your fantasies of political explanations for scientific reality ?

  • wangweilin

    I’m conservative and believe that global warming is occurring–anybody can look at temperatures since the last ice age and see it’s warmer. As to the current alarm over something that’s happened before and will happen again, I think by looking at the multiple failed predictions from people like Holdren and Hansen you have to conclude the current efforts to create a catastrophic narrative are animated by politics and personal aggrandizement. After all if Gore, et al really believed what they were saying would they have multiple mansions, private aircraft and a high carbon output lifestyle? Recent stories of planet wide greening due to CO2, which by the way is not the major greenhouse gas, are the other side of the coin.Two sides to the story, one political the other factual. Do a historical search of climate doom news from the 1800’s to present and you’ll find the narratives repeating and failing then re-appearing again. The earth has been warmer…the earth has been cooler…it will be warmer again…it will be cooler again…it’s all in the geological record. Maybe the current crop of true believers have a stronger than usual Messiah complex.

  • wangweilin

    The picture at the top of the story would be more appropriate for poor agricultural practices. Nice subliminal suggestion though.

NEW ON DISCOVER
OPEN
CITIZEN SCIENCE
ADVERTISEMENT

D-brief

Briefing you on the must-know news and trending topics in science and technology today.
ADVERTISEMENT

See More

ADVERTISEMENT

Discover's Newsletter

Sign up to get the latest science news delivered weekly right to your inbox!

Collapse bottom bar
+