Summary: Alarmists went hysterical about the warming during the 2015-16 El Nino. In October the decline began from that spike. The climate policy debate might depend on what the world’s temperature does during the next year or so. Will the pause continue, or will warming resume? Here are several perspectives on the current warming, provided by NOAA and NASA.

“It is extremely likely (95 – 100% certain) that human activities caused more than half of the observed increase in global mean surface temperature from 1951 to 2010.”

— One of the most important conclusions of IPCC’s AR5 Working Group I…

This statement about past warming is important. But for making public policy decisions future warming we need to know the odds of various amounts of warming during the 21st century. There is no easy answer to this, let alone a consensus of climate scientists about it. So climate activists either ignore the research (such as the 4 scenarios described in AR5) or focus on the worst of these (the truly horrific RCP8.5) while ignoring its unlikely assumptions.

So far the weather has sided with the skeptics, with little of the extreme weather activists predicted. No surge of hurricanes after Katrina (despite the predictions). No sign of the methane monster. Northern hemisphere snow extent has risen since in both the Fall and the Winter. There is little evidence that we have passed one of the often declared “tipping points”.

So it is logical that — despite the efforts of government agencies, academia, and many ngo’s — the public’s policy priorities have been unaffected (details here). Republican control of the Presidency, Congress, and most States makes policy action almost impossible for the next 4 years (ceteris paribus). As a result, activists are going thru the 5 stages of grief for their campaign.

Current trends: what’s the weather doing now?

Both sides in the public policy climate wars obsess over short-term weather, even local weather. They rejoice over statistically insignificant changes in the global average temperature. They celebrate record highs and lows in obscure corners of the world. But there is a gram of sense in this, as short-term (decade long) trends have had great influence on the policy debate — and might bring decisive victory to either side (no matter what the climate does by 2050).

There is no one true way to show trends in global temperature. Bob Tisdale produces a detailed monthly analysis. Here are some perspectives better suited for the general public. First, a graph by NOAA (excellent, as usual) clearly showing the trend since the reliable instrument era began in 1880. This graph exaggerates the flatness because warming is concentrated in months of May, June, & July. Click to enlarge.

NOAA: Global surface temperatures for month of November.

Flattish for 13 years, except for the 2015-16 El Nino spike.

Despite “skeptics'” claims, there is nothing unusual about the recent cooling. It’s the commonplace downside of an El Nino spike. Despite activists’ claims, the pause (about which climate scientists have written so much) continues.

For another perspective, see the lower troposphere temperatures recorded by satellites (prepared for NASA by U AL-Huntsville). The below graph is by lead scientists Roy Spencer. It tells a roughly similar story. Showing the full time series gives more detail than the above graph — with more noise. Again an El Nino spike, followed by a drop. But not yet a drop to the pre-El Nino level. Click to enlarge.

Long ago Roger Pielke Sr. said that the best measure of global warming is the total heat content of the world’s oceans. He was called a “denier”. Now ocean heat content (OHC) is a consensus measure of warming used by climate scientists. NOAA posts this graph of annual OHC, showing the temperature anomaly vs. the reference period 1955-2006. OHC is little affected by the weather, and clearly shows the gradual warming since 1970.

Ocean heat content, the best measure of global warming, rising slowly since 1970.

The future: alarmists win if we get several bouts of extreme weather

“Men will seem to see new destructions in the sky. … O! marvel of the human race! What madness has led you thus!”

— From The Notebooks of Leonardo Da Vinci .

There are always bouts of extreme weather, such as the California drought now running with no end in sight. So far the pause has trumped alarmists’ stories about these events (see scientists’ papers about the pause, the debate about its causes, and predictions of its duration).

But public opinion might change if the US gets hit by several at once, or some of unusual intensity, or they hit vulnerable areas. For example, we have had no landfalls by major hurricanes since 2005 — the longest such period on record. Cities from Miami to New York are absurdly vulnerable (we’ve spent our infrastructure money in Afghanistan and Iraq). Imagine if they are hit. No matter what the scientists of NOAA say the next day (e.g., time is needed for study because attribution of weather is difficult), journalists’ microphones will go to activist scientists announcing their insta-verdicts — CO2 is responsible.

For More Information

If you liked this post, like us on Facebook and follow us on Twitter. For more information about this vital issue see the keys to understanding climate change and these posts about the politics of climate change…

To learn more about the state of climate change…

…see The Rightful Place of Science: Disasters and Climate Change by Roger Pielke Jr. (Prof of Environmental Studies at U of CO-Boulder, and Director of their Center for Science and Technology Policy Research).