Post by Dr. Ryan N. Maue
Dr. Judith Curry is quoted in a classic Seth Borenstein AP screed connecting disparate extreme weather events into a tidy AGW-narrative: “Sometimes it seems as if we have weather amnesia.” …Judith Curry of Georgia Tech disagreed, saying that while humans are changing the climate, these extremes have happened before, pointing to the 1950s… she is correct but just who/what is she disagreeing with?
The AP article sets up the typical “arguing amongst experts” debate where the non-expert journalist assembles the narrative.
The AP article begins:
“Nature is pummelling the United States this year with extremes. Unprecedented triple-digit heat and devastating drought. Deadly tornadoes leveling towns. Massive rivers overflowing. A billion-dollar blizzard. And now, unusual hurricane-caused flooding in Vermont. If what’s falling from the sky isn’t enough, the ground shook in places that normally seem stable: Colorado and the entire East Coast. On Friday, a strong quake triggered brief tsunami warnings in Alaska. Arizona and New Mexico have broken records for wildfires.”
Of course we know that natural disasters occur globally, and are often modulated by the El Niño Southern Oscillation (e.g. El Niño and La Niña). This is not new science and it is not controversial. All climate scientists should understand this natural variability and be able to discuss the teleconnections and atmosphere-ocean feedbacks historically observed in previous strong El Niños and La Niñas since the 1950s. For instance, a major long-lasting La Niña occurred in the 1950s which left Texas with a historic, record drought. The Texas State Climatologist Dr. John Nielsen-Gammon mentions this often in his media correspondence. The strongest La Ninas lead to Texas droughts. The 2010-11 La Nina led to the Texas drought of this spring and summer. It is not immediately clear how the few tenths of a degree in global warming may have changed the character of this drought compared to the 1950s. Scientific research is required to answer this question — which should be published in the peer-reviewed literature. On the spot expert testimony often turns out to be incorrect as Mother Nature continues to operate contrary to conventional wisdom.
Dr. Jeff Masters, owner (blogger) of private weather forecasting company Weather Underground is first quoted: “I’m hoping for a break. I’m tired of working this hard. This is ridiculous. I’m not used to seeing all these extremes all at once in one year.”
I’m sure Masters is tired of the website hits and advertising revenue, but this statement is not scientific but anecdotal. To my knowledge, Masters does not generate peer-reviewed scholarship as I have not come across a paper written by him. Examining the 1910s, 1950s or 1970s for similar frequency of extreme events may surprise many including him.
The AP article continues:
“What’s happening, say experts, is mostly random chance or bad luck. But there is something more to it, many of them say. Man-made global warming is increasing the odds of getting a bad roll of the dice. Sometimes the luck seemed downright freakish.”
Who says what? I request a roll call vote. Man-made global warming has not been explicitly connected to any event of 2011. The evidence or proof of this statement has not (yet) been created, published, or disseminated. Similar statements were made with respect to the Russian Heat Wave and Pakistani Floods of 2010 as well as the record cold winters of 2009-10 and 2010-11. Again, without concrete and rigorous research, that statement is anecdotal especially with the nebulous usage of “experts say” and “many of them say”. Who?
The insurance company Munich Re calculated that in the first six months of the year there have been 98 natural disasters in the United States, about double the average of the 1990s.
How does this compare to the 1910s, 1950s, 1970s, 1980s, or 2000s? Perhaps the 1990s were especially quiet when it comes to US natural disasters. Again, a little context would help.
“I think this year has really been extraordinary in terms of natural catastrophes,” said Andreas Schrast, head of catastrophic perils for Swiss Re, another big insurer.
Yes, it has been extraordinary — but why? Is it perhaps the record strong La Niña?
One of the most noticeable and troubling weather extremes was the record-high nighttime temperatures, said Tom Karl, director of NOAA’s National Climatic Data Center. That shows that the country wasn’t cooling off at all at night, which both the human body and crops need.
“These events are abnormal,” Karl said. “But it’s part of an ongoing trend we’ve seen since 1980.”
Dr. Karl’s quotes are likely out of sequence. Nighttime temperatures were indeed warm, but there clearly is a meteorological or climate explanation for this. Karl apparently says this: “Individual weather disasters so far can’t be directly attributed to global warming, but it is a factor in the magnitude and the string of many of the extremes, Karl and other climate scientists say.”
So, let’s summarize: if individual weather disasters cannot be directly attributed to global warming, then what on earth is causing them? Hello? Anyone?
NASA’s Dr. Gavin Schmidt to the rescue?
While the hurricanes and tornado outbreaks don’t seem to have any clear climate change connection, the heat wave and drought do, said NASA climate scientist Gavin Schmidt.
Well, that doesn’t narrow it down much. Some events can be attributed to global warming but some can’t. We need a list.
This year, there’s been a Pacific Ocean climate phenomenon that changes weather patterns worldwide known as La Niña, the flip side to El Niño. La Niñas normally trigger certain extremes such as flooding in Australia and drought in Texas. But global warming has taken those events and amplified them from bad to record levels, said climate scientist Jerry Meehl at the National Center for Atmospheric Research.
Dr. Meehl contends, according to the AP article, that AGW has exacerbated the effects of the historic La Niña from bad to worse. That is a testable hypothesis and likely further research could answer that claim. Until then, it is just that, a hypothesis. But, at least we have La Niña mentioned. However, the way the article is written, it seems as if Masters, Karl, and Schmidt knew nothing of the historic La Niña.
Now we come to Dr. Curry:
Judith Curry of Georgia Tech disagreed, saying that while humans are changing the climate, these extremes have happened before, pointing to the 1950s.
“Sometimes it seems as if we have weather amnesia,” she said.
Disagreed with what/who? Her reference to the 1950s harkens back to a time when Texas droughts and East Coast hurricanes were the norm — extreme events occurring with unprecedented frequency and ferocity. It is also a time when the Pacific Ocean was in a “cool phase” of the Pacific Decadal Oscillation [PDO] while the North Atlantic was in the middle of a warm Atlantic Multidecadal Oscillation [AMO] phase. Pacific cold — Atlantic warm. It’s a story we’ve heard Joe Bastardi telling on television for months now as we have returned to such a warm-cold ocean basin asymmetry.
The final expert NOAA’s deputy chief Kathryn Sullivan provides nice anecdotes, but no substance.
Thus, as the 2010s continue on — with the winter of 2011-12 likely being at least a moderate La Niña year (and cold as hell) — expect more weather and extreme events like the 1950s.
Hopefully our weather amnesia does not cause us to be ill-prepared for winter 2011-12.