Perhaps you saw yesterday’s headlines about 2016 being the planet’s hottest year in recorded history, according to both NASA and NOAA, and wondered if that wasn’t actually last week’s news. Or whether this isn’t a record that nowadays is broken every year.
Well, no. Last week’s news was actually just about temperature data for the United States, which saw its second-hottest year on record in 2016 (although Alaska, by itself, did set a new high).
As for this being an annual event, it’s true that 16 of the 17 hottest years have indeed occurred in this century, and the temperature trend line is certainly upward. But year-to-year variation still keeps keep each new year from automatically outdoing its predecessor.
What’s most alarming, maybe, about the 2016 global temperature data is that they erase a previous record set only in 2015, and 2015 broke the record set in 2014.
To have three record-breaking years in a row for global temperatures is highly unusual — it apparently has happened only once before, in 1939-41, whose temperatures now seem quite mild.
This has made for intense discussion and unusually, um, hot commentary among climate scientists. Here’s how David Titley of the Penn State Center for Solutions to Weather and Climate Risk chose to frame our planetary predicament:
We are heading into a new unknown. It’s like driving on a new road, at night, at speed, without headlights, and looking only through the rearview mirror.
Titley then sort of jumped the shark by making a silly comment about hoping we didn’t run into Thelma and Louise.
But Louise might actually have had the grace and the guts to take the ditch. We Americans, with the rest of the world in the back seat, are on a collision course with a president-elect who has denied the reality of climate change, then sort of partway taken back his denial, while giving no sign of considering the question important.
Anyway, that’s the sort of detail a CEO can comfortably leave to executive underlings, in this case a Cabinet-in-waiting populated by people who share a loyalty to industrial sectors invested not just in business-as-usual but in business-as-it-was-before-Obama.
Broad agreement on the data
Climate data are analyzed slightly differently by the National Aeronautics and Space Administration and the National Oceanic and Atmospheric Administration, but not so differently that their agreement this week is in itself noteworthy.
However, it’s worth pointing out that a similar assessment has now been reached by the UK Met Office, whose records go back farther, and reports indicate that the Japanese Meteorological Agency has been reporting data that concur as well.
Key excerpts from the NASA announcement:
Globally-averaged temperatures in 2016 were 1.78 degrees Fahrenheit (0.99 degrees Celsius) warmer than the mid-20th century mean. This makes 2016 the third year in a row to set a new record for global average surface temperatures.
The planet’s average surface temperature has risen about 2.0 degrees Fahrenheit (1.1 degrees Celsius) since the late 19th century, a change driven largely by increased carbon dioxide and other human-made emissions into the atmosphere.
Most of the warming occurred in the past 35 years, with 16 of the 17 warmest years on record occurring since 2001. Not only was 2016 the warmest year on record, but eight of the 12 months that make up the year — from January through September, with the exception of June — were the warmest on record for those respective months. October, November, and December of 2016 were the second warmest of those months on record — in all three cases, behind records set in 2015.
For context, there has long been agreement among scientists studying such questions that the upper limit of safety for these temps is about 2 degrees C. from 19th-century levels, and that keeping the increase under 1.5 degrees C. would be a lot better; the latter is the target adopted in the Paris climate accord signed in December.
Which means that as of last year we’d used up more than two-thirds of the conservative and internationally agreed-upon safety margin, and more than half of the worst-case limit.
For a longer historical perspective, consider this observation from the UK Guardian, whose reporting on the new climate findings is as usual among the best:
Direct temperature measurements stretch back to 1880, but scientific research indicates the world was last this warm about 115,000 years ago and that the planet has not experienced such high levels of carbon dioxide in the atmosphere for 4 million years.
How record warming shows up
So what was the hottest year on record like around the world? For that we turn to NOAA’s listing of “selected significant climate anomalies and events in 2016,” including:
- National high-temperature records in India (Phalodi on May 19, at 123.8 F) and Iran (Delhoran on July 22, 127.4 F)
- Deep droughts in southern Africa for the second year in a row.
- In Canada, the wildfire at Fort McMurray in Alberta that became the costliest natural disaster in national history.
- In the Arctic, the smallest annual maximum extent for sea ice for a second year running, and the second smallest minimum on record.
- In Hawaii, tropical cyclone Darby became the second in three years to make landfall; there have been only five since record-keeping began in 1949.
- In Australia, the fourth-warmest year on record; seven of the 10 warmest have occurred since 2005.
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And how will the world respond? The Washington Post put that question to 15 climate scientists and got the driving-in-the-dark comment quoted and linked above, as well as these others:
I fear this news will become like the car alarm at the mall. It just keeps happening but no one pays attention. … Yes, the climate changes naturally. … Yes, climate scientists know about urban heat islands, El Niño, and other things that modify temperature. … But no, these oft-cited retorts don’t change the fact that our climate is changing, in part, due to some human steroid on top of that natural variability, and it is affecting “kitchen table” issues: agricultural yields, national security, public health, water supply, insurance claims from disasters, and so forth. — Marshall Shepherd, director of Atmospheric Sciences Program, University of Georgia.
The conditions experienced in the past year has had some unusual and unique aspects to it because of the super-El Niño event, but it shows us the sort of thing that will become routine in a decade or so. This includes record numbers and record intensity of hurricanes and typhoons, record wide spread heavy rains and flooding (think Houston, Louisiana, the Carolinas (Hurricane Matthew), and now California), record drought, heat waves and wild fires, and increasing inundations in coastal regions from rising sea level. The costs from the added boost from global warming are in the tens of billions of dollars each year.— Kevin Trenberth, climate scientist, National Center for Atmospheric Research.
Like frogs in boiling water, record-breaking years seem normal to many of us, now. And just like a frog, the time for us to heed these warnings is now. It’s true that some amount of future change is inevitable, the result of all carbon we’ve spewed into the atmosphere over the past hundred years and more. But today, our future is in our hands and we have a serious choice to make.
Are we going to do our best to roll back the clock, prop up and support dirty energy, keep it going until its last gasp? Or will we join the rest of the world — led by China and India — in the new clean energy “moon race,” to a world where we’re powered by wind, sun and tides that don’t pollute our air and will never run out on us? — Katharine Hayhoe, professor of atmospheric science, Texas Tech.