Climate Change, July, 2023: Not the Mild Good News I Had Hoped For

Disclaimer:  I am now retired, and am therefore no longer an expert on anything.  This blog post presents only my opinions, and anything in it should not be relied on.

This April (after a long hiatus from blog posting) I hoped to be able to post a climate change piece with a few bits of good news among the bad.  CO2 as measured at Mauna Loa, it appeared, had cut its year-to-year growth rate nearly in half.  The use of solar power rather than coal or oil for energy in homes and cars was slowly growing as price drops for solar continued and the US passed the Inflation Reduction Act with incentives for solar and electric-vehicle use, as well as embedding climate change efforts more deeply in the US government bureaucracy.  Arctic sea ice appeared for the last six years to have reached a new equilibrium level, never breaching the 2016 lows.

And then, from April to July, several things happened almost simultaneously:

1.       James Hansen et al published a paper arguing that (a) global warming for a doubling of CO2 was most likely to be not 4 degrees C as he had previously estimated, but 4.5 degrees C, (b) this would be increased by an inevitable decrease in human-caused aerosols starting a few years ago, and (c) it was now possible to project to some extent the degree to which this warming would happen over the next century.

2.       “Hothouse Earth”, by Bill McGuire, talks specifically about what we may expect in the next 30-50 years in particular, including a halving of global food production.

3.       Monthly CO2 (Mauna Loa) saw a very large rise in April, to a rate 3 ppm above April 2022, and May and June show similar jumps, while our best measure of yearly CO2 jumped to 421 ppm in June, more than 50% above its 1850 280-ppm baseline – implying, together with Hansen et al’s work, that 3 degrees C of global warming above that time period is now “baked in” and unavoidable.

4.       Global sea surface temperatures are now well into record territory, and sea temperatures around Florida are now around 95 degrees, hot enough to kill coral and some fish.

5.       Antarctic sea ice has diverged dramatically from recorded extents – since it is winter in the Antarctic, this means that warm winds from an incipient equatorial El Nino have prevented as much as 1/3 of historical sea ice refreezing.  It would seem inevitable that new record lows will continue to be set all the way to Antarctic sea ice minimum in late January, with follow-on effects on Antarctic land ice melting and hence ocean level rise.

6.       Dangerous air quality from Canadian wildfires has affected the northern US, while record heat, often around 110 F, is affecting the southern US.

7.       From July 3^rd to the 5^th, global record land temperatures for apparently the last 125,000 years occurred, reaching above 17 degrees C.

Looking Forward with Great Wariness

All of this is worrying enough.  But it is also the case that by all accounts, a new El Nino is starting, and may well last for a year or more.  The past few times an El Nino has occurred, if I remember correctly, CO2 has spiked upwards at a record pace and global land temperatures have also risen significantly.  The prospect of grueling heat waves not just this summer but next is certainly a cause for major concern.

I should also, I suppose, mention articles suggesting that the melting of permafrost with attendant methane release is continuing to ramp up.  It is not clear how much this increases global warming independent of CO2 increases:  methane (CO4) is more powerful in the atmosphere as a greenhouse gas, but much less prevalent than CO2.  At the same time, a certain amount of methane breaks down in the atmosphere to CO2, thus increasing carbon dioxide concentration.

Overall

My conclusion from all of the above is that most if not all of our decrease in CO2 emissions is being “drowned out” by the shift to El Nino, economic rebound from COVID, decreases in aerosols, and increased permafrost melting. 

One good thing is that popular news outlets aside from The Guardian – including CNN, AP, and the New York Times – are willing to report that today’s weather extremes are indeed caused by climate change.  On the other hand, I see not only that 150-odd Republican Representatives (a majority of Republicans in the US House of Representatives) are still classed as “climate deniers”, but also that an increasing number of people at the other extreme have given up hope of doing anything about climate change – often because they sense correctly that the 1.5 degree C target for “avoiding disaster”, and also the 2 degree target for “avoiding catastrophe” are certain to be overrun.

However, this, I must emphasize, is not, in my view, the proper way to view the future.  What lies beyond these targets – the next doubling of CO2, and the next – increases the scale of the disaster almost tenfold.  It is true, I think, that once one target is breached, the next is harder to stop short of, because both of feedbacks from initial warming and increasing sunk costs of fossil-fuel infrastructure that makes its replacement harder.  However, those feedbacks decrease over time to nothing if we succeed in slowing CO2 emissions dramatically, and the success of solar power shows that green energy can succeed even if it means uprooting what’s there for a whole new system.

And so, our initial successes count far more towards preventing disasters numbers 2 and 3 than they do towards avoiding today’s disaster; and the consequences of success or failure in our quest are far greater.  Think 2 billion lives lost or 8 billion rather than 500 million and that may give you an idea of what is at stake.   Thus, what is happening is a matter for heartbreak and anger at those responsible, but not for despair.  On the contrary, it is a matter for steadfast effort. 

As was once said, it’s the only game in town, and you lose no matter what you do.  But if you do it right, you won’t go broke before the game ends.  Or, to put it another way, humanity and nature will not by and large die if we try well enough, although we cannot prevent mass murder, both before and after we die.  And that’s the best obituary we can hope for.