The U.S. climate became afflicted by split personality disorder in 2018

By Tom Yulsman | February 8, 2019 12:07 am

Meanwhile, the Earth as a whole continues to ride the up-escalator of human-caused global warming

2018: climatic split personality

2018 was the fourth warmest year on record globally, part of a decades-long warming trend. (Source: NASA Goddard Media Studios)

Two U.S. agencies have reported on how Earth’s climate fared in 2018. For the most part, the news wasn’t all that surprising: The long-term trend of human-caused global warming showed no significant signs of relenting.

But I was surprised by one finding: The United States experienced something of a split climatic personality last year.

More about that in a minute. First, though, NASA and the National Oceanic and Atmospheric Administration announced yesterday that Earth experienced its fourth warmest year in records dating back to the late 1880s.

“Across the globe it was extremely warm, with only a few places that were slightly below normal,” observed Gavin Schmidt, director of NASA’s Goddard Institute for Space Studies, during a phone briefing with reporters that I participated in. The planet continues to warm over the long term, and “it’s because of the greenhouse gases we’ve put into the atmosphere in the last hundred years.”

2018: climatic split personality

Yearly temperature anomalies from 1880 to 2018, with respect to the 1951-1980 mean, as recorded by NASA, NOAA, the Japan Meteorological Agency, the Berkeley Earth research group, and the Met Office Hadley Centre (UK). All five show peaks and valleys in sync with each other, along with rapid overall warming overall.
(Source: NASA Earth Observatory/Joshua Stevens)

Deke Arndt, chief of the monitoring section at NOAA’s National Centers for Environmental Information, likened what’s happening to “riding up an escalator over time and bouncing up and down on that escalator.” The ride up is global warming, while the bouncing up and down are natural climatic variations caused by such phenomena as El Niño (which tends to cause warming) and La Niña (which cools things off).

As seen in the  animation above, five independent analyses agree on the details of that metaphorical escalator ride — a striking concurrence.

But I found the analysis of what happened climatically in the United States last year even more striking.

The nation experienced it’s 14th warmest year in a record stretching back 123 years. That puts 2018 in the top 10 percent of warm years nationally.

Noteworthy, for sure. But much more so was the pattern of U.S. climate anomalies in 2018.

U.S. climate in 2018: split personality

As seen in the map above, the Northern Plains and parts of the Upper Midwest were among those few places globally that were a little cooler than normal last year. But in stark contrast, much warmer than average conditions prevailed from the Rockies all the way west to the Pacific Ocean.

And when it came to precipitation, the dichotomy was even more dramatic:

U.S. climate in 2018: split personality

Overall, the United States experienced its third wettest year. You have to go all the way back to 1983 to find a wetter one.

But in the graphic above, check out the stark contrast between the United States east of the Rockies and west of the Rockies.

The eastern two thirds of the country were exceedingly wet in 2018 — and nine states actually experienced their very wettest year on record. According to NOAA’s Deke Arndt, climate change played a role, in this way: The warming has allowed the atmosphere to carry more water vapor, and thus the storms that hit the eastern part of the country dumped even more rainfall than they would have otherwise.

Meanwhile, the western third was mostly dry — and some parts of the region were really dry. As Arndt put it: “ There is an entrenched and very intense drought, frankly, in the Four Corners region.”

U.S. climate in 2018: split personality

Drought is not just about the amount of precipitation that falls from the sky. Other important factors contributing to drought include temperature and soil moisture.

Considering those and other factors, the situation in a broad swath of the southwestern United States was quite bleak in 2018. In the map above, all the areas colored in dark brown were considered in drought for every single week of the year.

This is a continuation of very dry conditions dating back to the beginning of the 2000s. This drought, and increasing demand for water, have caused water levels in Lake Powell and Lake Mead — the two giant reservoirs on the Colorado River — to drop significantly. This has raised fears of coming water shortages in the Colorado River Basin, from which 40 million people in seven states draw water.

With this in mind, I asked both Arndt and Schmidt whether they thought the dry conditions were indicative of an emerging new normal for the region. Arndt was fairly cautious in his response: “In the late 1990s, we entered into a persistent period in which the extent, intensity and frequency of drought have increased. But I am not prepared to say that this is the new normal.”

Schmidt went further. He said that in the context of the paleo record, meaning the past 1,000 years or so, the recent dearth of precipitation may not be that unusual. “But the drying that we get in the soil bed from increasing temperatures — that has actually been a significant factor in the intensity of the drought and their impacts.”

In this way, human-caused climate change is contributing to ongoing drought in the region. And barring increases in precipitation — which climate models do not predict for the Southwest — drying will continue as temperatures warm further.

  • Occasional-Cortex

    Time for the region to intelligently adapt to gradually changing circumstances caused by global, not local, greenhouse gas emissions. Water use, forest management, agriculture and other policies. Definitely forest management.

    For a variety of reasons the total amount of greenhouse gasses in the atmosphere is likely to increase for the foreseeable future. That total is the sum of the economic activity of all the countries in the world. As a result, any actions taken locally might mitigate air pollution but not not local climate change effects such as described here.

    The United States produces just 14% of global greenhouse gas emissions, the South West just a portion of that. Reducing the amount of greenhouse gas produced by the South West – or even the country as a whole – is a good idea but not a solution to the region’s problems, as many incorrectly believe. If you only control a fraction of 14% of a problem how much effort can you realistically have?

    • Nom de Plume

      How would anyone know they were making the right decisions? I’m reminded of one town in the northern US who was so convinced that cold weather wouldn’t be a thing than they planted trees that thrived in warmer climates. A better decision would have been to select trees that tolerate a wider temperature range, so that they would be good to go regardless of swings in temperature. I don’t know how things worked out for that town, but suspect it went about as well as when a lemon tree I set out turned out not to be as cold hardy as I thought.

      • Occasional-Cortex

        They seem to definitely need some work on forest management and water use for starters.

    • Mike Richardson

      This is the same thing you’ve posted repeatedly in other blog article comment sections. We’ve already been over this. China is expanding their renewable energy, and should be encouraged to do so instead of relying on coal and fossil fuels, though this apparently would disappoint you. The United States should also try to lead by example, for whatever we do, China and other countries usually imitate and attempt to compete with. Unfortunately, listening to voices like yours and electing national politicians that repeat the same rhetoric, we have currently ceded that leadership to other nations, as well as state and local governments here. For the good of civilization, that needs to change.

      • Occasional-Cortex

        So I guess China, India and the other less developed nations who contribute over 2/3 of greenhouse gasses are going to decide to slow or forgo economic development for their people by abandoning carbon in order to satisfy what Western greens think is good for them? As if they want to imitate us to win a global popularity contest. Seriously?

        This is the part about the greens that amazes me, the utter ego-centrism. Oblivious to the cold fact that billions of people in developing countries could care less what Westerners think about how they should live or what aspirations they should have.

        They will “imitate” us when when there is a way to produce energy to drive their economies that is more cost effective than carbon.

        China is expanding solar primarily because their high sulfur coal is so hazardous to health, even though solar is far inferior in cost / energy output.They are trying to mitigate health costs with a more expensive, less reliable source of energy. But that certainly does not mean they are abandoning carbon or trying to switch over their economy to windmills and solar panels. Because they have an actual grasp of physics and engineering.

        Unlike the towering intellects who recently put forth the “Green New Deal”. It’s like reading a parody on “The Onion”.

        • Mike Richardson

          “So I guess China, India and the other less developed nations who contribute over 2/3 of greenhouse gasses are going to decide to slow or forgo economic development for their people by abandoning carbon in order to satisfy what Western greens think is good for them?” — You offer a false choice here, stating that investment in renewable energy technology would “slow or forgo economic development.” These technologies are creating investment opportunity and growth everywhere they are being developed, without creating significant pollution or contributing so much to the buildup of greenhouse gases in the atmosphere.

          Your fossil fuel industry talking points are getting stale, and your username, avatar, and statements about “Greens” clearly indicate where you are coming from politically. You do not wish to see fossil fuels displaced, either due to economic or political motivations, or more likely a combination of both. You at least have conceded that there is a problem with greenhouse gases and climate change, though you demonstrate that the position of climate change “skeptics” has simply evolved to denying that the problem can be addressed in any meaningful way. That is defeatist, and not a realistic counter proposal to the New Green Deal or any of the other more modest plans to address climate change and grow the economy. I prefer realistic optimism myself, and action rather than cynical excuses furnished by the industry that has helped create the problem.

          • Occasional-Cortex

            Right, I collect a big check from the guy who looks like the Monopoly Man at the Fossil Fuel Industry Check Issuing Department. Ya got me!! LOL

            As opposed to pointing out the scientific illiteracy and economic inanity of the loony left’s Green Great Leap Forward. Which has already generated a detectable increase in CO2 from forehead slapping ,uncontrollable belly laughter.

            Before we launch into our brave new green world based on the well conceived plans of a recent bar maid who has calculated that we have just 12 years to live, maybe we should actually examine the experience of say, Germany, for starters. Which now guzzles more gasoline and coal than ever because of failed, half baked far left green idiocy.

            I prefer realistic optimism myself. Not apocalyptic catastrophism, call me a skeptic. Or a grab bag of worn out left wing cliches now incoherently repackaged and repurposed as environmental…?? You can’t say “policy” because that actually involves a rational plan of some sort from A to Z. Meme generator? Bumper sticker ideas?

          • Mike Richardson

            So your opposition is based primarily on right-wing political ideology, and not financial gain. Thanks for the confirmation!

          • Occasional-Cortex

            And your optimism is based on socialist economics, because it’s worked so well everywhere it’s been tried.

          • Mike Richardson

            You mean like Finland, Norway, Denmark, Sweden, Canada, Ireland, New Zealand, and Belgium? Though democratic and possessing free markets, they have extensive social welfare systems and high standards of living. You really aren’t helping your cause here. Might want to occasionally engage that cortex in some critical thinking before putting words on the screen, right?

            But feel free to offer some capitalist suggestions of your own, other than doing nothing. If you can’t, don’t be surprised that younger people turn to another system that actually seeks to address the pressing problem of our day.

  • Nom de Plume

    Sigh. As variable as the climate change articles on Discover. After a good one this week, we have this. It isn’t helped by the fact that one study several years ago showed that climate change models had less accuracy than a random walk (search for the article, and find it in the original publication, and not secondary sites, where you’re certain you’ve got the real deal).

    The big thing on this one is that megadroughts in the SW US are known to have happened before. Doubt it? Look for the 200 year drought that happened in the Sierra Nevada from the 9th into the 12th centuries. Or look into the US SE where dunes arose when drought dried up rivers and prevailing winds blew the sand out of the channels.

    Screaming “It’s AGW!” at every single event isn’t science. Examining actual data and how well it fits or refutes a theory is. And models are just that: models of how we think things work. If a model fails to accurately predict past and future events, it means how we think things work isn’t quite the way it is. Which takes us right back to that aforementioned study.

    It also gets into an idea for modeling on the cheap. Believe in AGW? Fine: Look at what happened the last time temperatures were at a certain level while our continents were in this configuration. This is more of a “Check the book” method than actual modeling, but might work better, at least for now.

    • Renewableguy

      There are statistical methods to see how much chance there is of an event happening based in 280 ppm co2. Some weather events just can barely occur in that scenario. And they occur more often than in the lower co2 and lower energy content of the earth at that time.

      • Nom de Plume

        This goes back to looking at actual history, which was my point in another thread. My point in this one is that it seems they looked mostly at temperature, and called it a day.

    • Tom Yulsman

      To quote you, Mr. Nom de Plume, “sigh.”

      You must not have read the entire story. In it I make the point that drought is not just about the amount of precipitation that falls from the sky. It’s also about temperature and soil moisture. And if you had read the entire story, you would have seen what NASA’s Gavin Schmidt had to say about this. He noted that in the context of the paleo record, meaning the past 1,000 years or so, the recent dearth of precipitation may not be that unusual. You are indeed correct about this. But he went on to say that “the drying that we get in the soil bed from increasing temperatures — that has actually been a significant factor in the intensity of the drought and their impacts.”

      Observational studies, not computer modeling, have documented this increasing aridification due to warming. And even if higher levels of precipitation should return, the warming will continue, and thus, so will the drying.

      • Nom de Plume

        You didn’t look at the map, did you?



ImaGeo is a visual blog focusing on the intersection of imagery, imagination and Earth. It focuses on spectacular visuals related to the science of our planet, with an emphasis (although not an exclusive one) on the unfolding Anthropocene Epoch.

About Tom Yulsman

Tom Yulsman is Director of the Center for Environmental Journalism and a Professor of Journalism at the University of Colorado, Boulder. He also continues to work as a science and environmental journalist with more than 30 years of experience producing content for major publications. His work has appeared in the New York Times, Washington Post, Audubon, Climate Central, Columbia Journalism Review, Discover, Nieman Reports, and many other publications. He has held a variety of editorial positions over the years, including a stint as editor-in-chief of Earth magazine. Yulsman has written one book: Origins: the Quest for Our Cosmic Roots, published by the Institute of Physics in 2003.


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