September 15, 2015 11:35AM

You Ought to Have a Look: Carbon Sinks, Hurricanes, SETI

You Ought to Have a Look is a feature from the Center for the Study of Science posted by Patrick J. Michaels and Paul C. (“Chip”) Knappenberger.  While this section will feature all of the areas of interest that we are emphasizing, the prominence of the climate issue is driving a tremendous amount of web traffic.  Here we post a few of the best in recent days, along with our color commentary.

Over the past couple of days, several articles have caught our eyes that we thought worthy of a mention in these pages.

First up is a pair of papers, one by Swiss researcher Peter Landschützer and colleagues and the other by a team led by University of Colorado’s David Munro, that examined trends in the rate of carbon dioxide uptake in the Southern Ocean.  In each case, the authors report that carbon uptake has been increasing there during the 21st century. This is good news.

Carbon dioxide uptake is basically the opposite of carbon dioxide emissions. As emissions increase and the atmospheric concentration grows, this puts a pressure on some carbon sinks to expand—notably the standing biomass of vegetation (through carbon fertilization) and the carbon content in the oceans (through Henry’s Law). In fact, the proportion of human carbon dioxide emissions that are being taken up by carbon sinks has been pretty constant for the past 150 years—meaning the sinks are expanding to offset a significant portion of our growing emissions.

Even though the behavior found in the new research paper is confirming expectations, it is worth highlighting in that over the past couple of years several papers were published and subsequently rose to prominence suggesting that the rate of carbon dioxide uptake by the Southern Ocean was slowing down and this was an indication that the carbon sink there was saturating.  This had some segments of the climate alarmosphere in a tizzy (google “ocean carbon sink saturating” for some examples). The worry spiral went like this: CO2 emissions were leading to climate changes that were leading to less carbon update by the oceans which was leading to more CO2 in the atmosphere which was leading to more climate change which… you get the point.  Uncontrolled positive feedback.

The new findings pretty much stamp out this overheated concern.

From Landschützer et al.:

Several studies have suggested that the carbon sink in the Southern Ocean—the ocean’s strongest region for the uptake of anthropogenic CO2—has weakened in recent decades. We demonstrated, on the basis of multidecadal analyses of surface ocean CO2 observations, that this weakening trend stopped around 2002, and by 2012 the Southern Ocean had regained its expected strength based on the growth of atmospheric CO2.

And from Munro et al:

Overall, [our results are] suggesting that the Southern Ocean is playing an ever-increasing role in taking up atmospheric CO2.

So it seems that the apparent slowdown in the rate of carbon dioxide uptake in the Southern Ocean was most likely just a passing blip in what is natural variability—the level of which was previously underestimated. No cause for alarm.

Next up is a new paper by hurricane forecasters/researchers Phil Klotzbach, Bill Gray and Chris Fogarty examining the trends and natural variability in a key indicator of Atlantic hurricane behavior.  The Atlantic Multidecadal Oscillation, or AMO, has long been identified as a dominant influence on the frequency of hurricanes that form in the Atlantic Ocean. As its name suggests, the AMO “oscillates” back and forth between its positive and negative states with a time period of several decades. The AMO had been in a “positive” state—one that is conducive for hurricane development--since 1995. In their new paper, Klotzbach and colleagues present evidence that the AMO may have recently switched to a “negative” state—one that tends to hinder hurricane development. This would explain the dearth of hurricanes in the Atlantic Ocean for the past couple of years and would suggest that we are entering a prolonged period of below average activity.

Klotzbach goes into the details of what they found in a great article hosted by Washington Post’s Capital Weather Gang. That article begins:

Floyd, Katrina, Wilma, Ike and Sandy — just a few of the devastating hurricanes we’ve seen in the years since 1995. It’s been an astonishingly active hurricane period of the Atlantic Ocean, costing the U.S. over $500 billion in damages. But there’s evidence to suggest that the painfully memorable, two-decade era that brought some of the most intense hurricanes on record — and some the most active hurricane seasons — is coming to a close.

Not everyone is sold on the idea that the AMO is a real phenomenon and/or that it exerts a major influence on Atlantic hurricane activity. For example, is association with the extremely active hurricane seasons of 2004 and 2005, several research papers were published and subsequently rose to great prominence, that suggested that rising sea surface temperatures caused by human greenhouse gas emissions were the cause of the observed upswing of hurricane activity—with things only to get worse in the future.  The subsequent downturn of hurricane activity, including the on-going (and expanding) record period of time between major hurricane landfalls in the U.S. (which is fast approaching 10 years) has vindicated the AMO and those researchers, like Klotzbach and Gray,  who have identified its influence (although there are still some holdouts, as MIT’s Kerry Emanuel, who told AP reporter Seth Borenstein  in regards to the new study “I think they're pretty much wrong about this”).

Klotzbach says that time will tell for certain.

And finally, we come across what we think has to be the most unusual suggestions as to how to handle the climate change issue—ask aliens.

Apparently there is something called the Breakthrough Message contest in which a million dollars in prizes will be awarded  for “messages that could be read by an advanced civilization.” The Breakthrough Message sponsors want to “encourage debate about how and what to communicate with possible intelligent beings beyond earth.”   

In response to the contest, a group of U.K. researchers dedicated to the search for extraterrestrial intelligence (SETI) have decided to submit an entry. They have yet to agree on what their message will contain, but the group’s spokesman told the BCC:

“[We] also know that our own civilisation is in a fair bit of trouble. We face some pretty big threats. That means it might be a good idea to gamble, and hope there is someone slightly older and wiser out there. If aliens told us something about how to handle our climate, or artificial intelligence, we might want to listen."

We resist any comparison to the Papal Encyclical.