One thing about using a treadmill… you can tell any difference in energy levels right away. I did 30 minutes on the treadmill both Monday and Wednesday, and the difference was striking. On Monday, I moved my reading material out of the way to do an “Are we there yet?” check and was surprised to see that it had only been 10 minutes; on Wednesday, I wasn’t moved to peek till 28 minutes. On Monday, I put the grade at a comfortable spot and found when I looked that it was 4.5; on Wednesday, I didn’t check how high I had put it, but when I moved it back down for cooldown, I was surprised to see that it was only down to 6, and I had to move it down more and cooldown a bit longer. On Monday I was slogging along, and on Wednesday I was dancing along.

I don’t know why. The weekend did involve less sleep, more sitting, and richer foods than normal, but weekends often do. I started my period on Wednesday, so I guess I was pre-periodic on Monday, but I never pay much attention to that. I was reading Smithsonian on Monday and Wired on Wednesday, so maybe the sheer modernity of the magazine made the difference. I don’t know. Maybe my improvement in Ubiquitously Capturing made me more light-hearted.

Actually, I like that term a lot, and the concept, too. I shared it with my study group yesterday. I used the coffee as the example. And then I actually left the church without buying any coffee. Clearly, there are still a few bugs in the system.

I caught a ride home with Janalisa. #2 son drove me there (with his learner’s permit and a growing grasp of how to keep the car in the right place, thank goodness) on his way to work, and then #1 son took the car and went to something called “Boogie Boulder” or “Bouldering Bop” or something like that. I am sure I have it wrong. There was alliteration, and it involved bouldering and then some word referring to music. It is the rock climbing equivalent of “Rock ‘n’ Bowl,” an event involving music and bowling which has been a teen mainstay around here for as long as I’ve had teens.

We were talking. I wasn’t thinking about coffee, and I didn’t look at my list. Oh, well.

Have you been wondering about what Peter Ward has to say about global warming and mass extinctions? I don’t think that most of you are going to read this book, so I don’t feel bad about revealing things as I get to the ending. There has been lots of suspense as we learn what paleobiologists and chemical geologists were thinking in the ’80s and then the ’90s, and now we are all the way up to the discoveries of the first years of the 21st century.

It has been largely proven, at least to my satisfaction, that the mass extinctions of the past were in fact caused by greenhouse gases, and that I can expect to live (assuming we do nothing about it) to see the extinction of 60% of the currently living species. We could be one of the extinct ones, of course, but in that case, I won’t live to see it. It is pretty impressive, I’d say, that Dr. Ward has argued this complex point in a combination of blank verse and graphs. His word picture of the Canfield oceans belching forth toxic gases on the Arizona coastline, under a pale green sky (I’m seeing it as chartreuse, but a faint avocado could also be very effective), will be with me forever, I am sure.

The startling new thing in the penultimate chapter is the suggestion that the earth might well have been on its way into another of its periodic ice ages, were it not for agriculture and industry. The jury is apparently still out on this one, but our world has never (according to the evidence of ice cores and sedimentary rocks) seen a rise in the concentration of greenhouse gases like the one we’ve produced since the beginning of the Industrial Revolution. And up to a point, it could have been good for us humans. Relative balminess is better than sheets of ice, and the last 10,000 years have been an unusually stable time for the climate of the earth.

But it is like a light switch, Ward suggests. However slowly you push it, the lights will not gradually come on. You will just slowly move toward the point at which the connection is made and the lights appear. If we compare our current world with its former conditions, it is clear that a tropical world is right around the corner.

Not for the the first time, of course. There are fossils of crocodiles and palm fronds up near the arctic circle. We’ve had a tropical world before.

Or rather, Earth has been tropical. We weren’t there at the time.

Ward makes the very intriguing claim that, even though people can and do live in places where heat and humidity both hover around 98 (degrees and percent, respectively), we aren’t any good at it. He points out the ubiquity of natural drug use (coca, betel nut, etc.) among people in tropical climes, and the lassitude of people who have to live in such places without air conditioning. I don’t know about that. I do know that the place where I live is like that for about six weeks a year, and before we had air conditioning, we could hardly do a thing when it was that hot, but I haven’t seen any scientific studies of this topic, and Ward doesn’t cite any.

So we’ll get all tropical, and it might not be good for us, and the coastlines and deltas will go under, taking much of our food supply with them, and then there will be so much of these greenhouse gases that it will not just be about heat any more, but about toxicity, oxygenated oceans (not a good thing), acidity, and dreadful poisonous death.

Ward isn’t talking much about the spell of wild weather and enormous storms which earlier books on the subject predicted, because we’re there right now, and there’s little point in predicting things that are already happening.

Current predictions, based on an assumption that we will not change our behavior, suggest that we will be seeing this next mass extinction around 2060.

Do you have grandchildren? If not, you probably plan to be alive in 2060, if the Lord tarries, as they say in the country churches around here. If your plans do not include either the Rapture or a great big change in how you use natural resources, you may be able to enjoy that green sky firsthand, or your grandchildren will.