I suppose I have to say something about the new IPCC science report that came out this week (I’m writing on Thursday, August 12). It’s easy to find summaries of it from actual journalists in the media, for example this one from the AP.

I’ve only read the summary for policy makers. I have the best intentions to read the full report, but then I had the best intentions to read the last 16 IPCC reports, not to mention the proliferating ecosystem and biodiversity reports. Anyway, if you don’t mind a collection of random observations, here are a handful of things that caught my eye:

• The graphics are kind of nice. If you are trying to communicate science-y or tech-y things to general audiences, they are worth a glance.
• If we stopped emitting carbon emissions today, the earth would continue to warm for decades, if not centuries or millennia. This means the effects we are feeling right now were caused by emissions decades ago. Emissions have not only continued for decades, but they have accelerated. Things are going to continue to get worse, and probably not linearly but exponentially. If we drastically cut emissions today, the results would be detectable in about 20 years or so. The Earth is a dynamic system with lags and feedback loops.
• Warming of about 1.5 degrees C (I don’t know how to make a degree symbol in WordPress) would be considered a great outcome. The Earth has already warmed by about 1.0 degrees as of right now (2019 actually).
• Human activity is the overwhelming cause of warming. Come on, don’t be stupid. Natural factors exist but they are small compared to the human activity.
• One thing that did surprise me is that scientists are pretty sure that human-caused air pollution has had a significant retarding (using this word in the scientific/musical sense of slowing something down) effect on global warming. But again, more than overwhelmed by the sheer magnitude of burning, burning, burning with reckless abandon for centuries now.
• Scientists are very sure human activity is driving massive ice loss in the Arctic. They are only kind of medium sure it is the main driver in the Antarctic.
• So what is a good place to live? Well, central and eastern North America are some of the only regions are Earth that are not unequivocally hotter already, meaning scientists disagree on whether they are or not. They are more at risk of flooding though, along with most of Asia. Drought is biting harder in western North America, parts of Europe, Central Asia, Africa, and southern Australia than elsewhere.
• There are five scenarios in this report. They are called SSP1-1.9, SSP1-2.6, SSP2-4.5, SSP3-7.0 and SSP5-8.5.

Compared to 1850–1900, global surface temperature averaged over 2081–2100 is very likely to be higher by 1.0°C to 1.8°C under the very low GHG emissions scenario considered (SSP1-1.9), by 2.1°C to 3.5°C in the intermediate scenario (SSP2-4.5) and by 3.3°C to 5.7°C under the very high GHG emissions scenario (SSP5-8.5)24. The last time global surface temperature was sustained at or above 2.5°C higher than 1850–1900 was over 3 million years ago (medium confidence).

IPCC

• Coastal property may not be a good investment.
• Scientists are divided on the tipping point theories involving the global meridional circulation. They agree it is going to weaken though. The tipping point collapse scenarios “can’t be ruled out and are part of risk assessment”. Ha – risk assessment language might say something like “unknown but non-zero probability, existential threat”.
• The report provides a remaining carbon budget that could be used for policy making, depending on the end point the world would like to target.