Climate Change - Speeding Past the Stop Signs

There's been a tendency in the media and in the international community to assume that with the Paris agreement this past December, the world is well on its way to dealing with the problem of climate change. In fact, the agreement was woefully inadequate, allowing for an increase of 3.5 C or more, and recent data suggests it's only gotten worse since the agreement was signed. Rather than feeling complacent, we should be doubling down on the very limited progress we made.

Bottom line: even with the Paris agreement, we may be running out of time to avoid losing virtually every coastal city and port in the world, among other things.

"Paris was a magnificent political achievement but it was woefully inadequate from the perspective of physics. And when it comes to a conflict between physics and politics, physics always wins." Let's take a look at what's happened since the agreement was reached.

Record Breaking Records

February was an astounding 1.35 C (2.43 F) warmer than the average temperature for February based on the period from 1951 to 1980. That smashed the previous record for a monthly temperature increase by .21 C, another record. Oh, and that previous monthly record? It was set in January.

To put the 1.35 C increase in perspective, the Paris Agreement recognized that a 1.5 C increase over pre-industrial levels posed serious threats and countries agreed "... to pursue efforts to limit the temperature increase to 1.5 degC above pre-industrial levels, recognizing that thiswould significantly reduce the risks and impacts of climate change ..." Worse, we've been above the so-called "guardrail" agreed to in Paris - 2 C above pre-industrial levels (as opposed to measuring against the 1951-1980 average) - for several months now.

The last ten months in row, by the way, have all broken such records. And March is set to break the record for the warmest March since records have been kept, which would break the record for the most consecutive monthly records set in a row in 1944.

Confused? Wait, there's more.

Last year, 2015, "smashed" another record as the warmest year on record. The previous record was set in 2014. According to NOAA, 2015 was a full .9 C above the 20^th Century average, and every forecast calls for 2016 to break the record once again.

Finally, the National Snow and Ice Data center announced on Monday that the Arctic sea ice maximum was the lowest it's been since records have been kept, breaking the previous record which was set - you guessed it, in 2014.

And while some of this record smashing can be attributed to the effects of a severe el Nino, that merely accents a trend that has been accelerating for decades now.

Two More Reasons for Concern

Two recent articles explain why the Paris agreement may be too little too late, and they should send a collective shiver throughout the planet.

The first was by James Hansen and it described in a peer-reviewed paper that he and 18 other distinguished climate scientists wrote that will be published in Atmos. Phys. Chem. The paper attempts to explain discrepancies between what the models we use to forecast the rate of climate change and its effects tell us - particularly on sea level rise and superstorms - and the observed consequences of temperature changes on these phenomena in the geologic record.

To put it more simply, when you look at what happened in geologic history when warming equal to the 2 C "guardrail" occurred, the observed consequences were far worse than what our models suggest. And the kicker is, today's human-induced warming is happening much faster than those in the geologic record.

The Paris agreement used the IPCC's estimates of sea level rise which put the upper limit, worst case, for sea level rise by 2100 at just 1.2 meters. The geologic record suggests it could be more than twice that, and that it could begin sooner. Hansen et. al. also point to evidence that the added energy from warming spawned massive superstorms that assaulted coastal areas with epic storm surges.

The combination of multi-meter sea level increases this century with superstorms would make our coastal cities unlivable, and undefendable.

Some scientists are criticizing the conclusions reached in this paper because they are not 100% "definitive." In short, they believe that we should continue to drift toward potential catastrophe until someone can conclusively prove it. But more prudent scientists and policy makers realize that the burden of proof falls on those who would defend the status quo, putting the future of our children and their children at risk.

The second article comes from Joe Romm, who explained why two apparently contradictory trends in climate data were, in fact resolvable.

The first trend was widely reported and concerned the fact that, for the second year running, 2015 CO₂ emissions were flat, even though the economy grew. This was widely hailed as real progress in our attempt to slow the steady march of climate change.

It wasn't, and here's why.

On March 9^th, NOAA reported that 2015 saw the biggest rise in atmospheric concentrations of CO₂ on record.

This begs a question. If emissions are static, why is the atmospheric concentration of green house gasses (GHG) accelerating?

The answer is simple, but not well understood by policy makers or the media.

As Romm notes, the atmosphere can be thought of as a bathtub, with GHGs flowing in, and GHGs draining out. Although the flows and "drains" - or sinks - vary slightly over the epochs, they are typically in equilibrium, which lends the system some stability. Beginning with the industrial revolution, humans began to add more carbon (as well as methane and other greenhouse gasses) at a faster rate, and the bathtub began filling.

And even though 2015 saw a leveling in the amount of human caused emissions, we are still adding more than the sinks drain, so levels will continue to go up.

But if we're not increasing the amount we're adding, why did 2015 set a record for the biggest increase in atmospheric concentrations ever observed?

The answer lies in the sinks, and it doesn't bode well for the Paris Agreement having the kind of impact we need.

Sinks include things that absorb or sequester carbon. Some of the major ones include forests and other biota, including the oceans, soils, and peatlands. Basically, because of warming, the sinks aren't functioning as well as they used to. For example, one of the largest terrestrial sinks - the boreal forests - have been devastated by disease and pests caused by warming, and now they are not taking in as much carbon as they used to. In fact, in some areas, they have become a source of carbon emissions, not a sink.

So even if we manage to turn the emissions down a bit, the bathtub will continue to fill faster because the drain is clogged.

But it gets worse. The sinks have already stored trillions of tons of carbon over the eons. In fact, fossil fuels are basically hundreds of millions of years of stored photosynthetic energy. One of the more sensitive sinks, permafrost, contains an estimated 1,672 gigatons of carbon (more than double the amount currently in the atmosphere), and due to rapid warming, it is releasing some of this carbon - much of it in the form of methane, a GHG that is 73 times as strong as carbon dioxide in the short term. There are other feedbacks at work, each serving to release more GHGs.

This compromising of the sinks may be one reason that most of our models - including those that the IPCC uses - haven't matched the observable geologic record, and that means we've grossly understated the difficulty of mitigating climate change.

Bottom line: Paris was a magnificent political achievement but it was woefully inadequate from the perspective of physics. And when it comes to a conflict between physics and politics, physics always wins.

We knew, even as we signed it, that the Paris agreement did not prevent dangerous anthropogenic warming, and could result in warming of 3.5 C or more - a guaranteed catastrophe. The latest data suggests that, absent additional action, that outcome has moved from probable to something approaching inevitable.

Scientists need to urge leaders to hold an emergency meeting of the world's nations within a year, designed to hammer out an agreement that responds to the physical realities of climate change, not one constrained by what we currently perceive to be politically possible.