Tag Archive: climate change


Frozen Planet: DVD Review

Frozen Planet DVD coverWhen I heard that the BBC was making a documentary about the Earth’s high latitudes, Frozen Planet, I knew I had to have the DVD if they made one. When stories appeared that the part on global warming would be cut for US audiences, I was horrified – and relieved when the Discovery Channel relented – at least partly. Since I do not have cable or satellite TV, I had to wait for the DVD. Finally it arrived and I have been watching it – when I have time between gardening, marketing and writing.

As you may have guessed from previous reviews, I adore David Attenborough and really don’t understand why so many of his nature programs for BBC have been released in the US with different narrators.

The first episode is a general overview, followed by one for each of the four seasons – but the seasons used: spring, summer, autumn and winter, are not the seasons as usually defined. In fact they are not well defined, but appear to be based on the weather rather than the usual spring = the period from the northward equinox to northern solstice in the northern hemisphere and from the southward equinox to the southern solstice in the southern hemisphere. Roughly, they seem to define the period of continuous (or at least very long) daylight as summer, that of continuous or very long night as winter, and the period of alternating daylight and dark as the transitional seasons – but even this is not well followed. Other ways of dividing the seasons may be the waning, absence, reformation and solidity of sea ice, or the melting, absence, buildup and universal presence of snow. All seem to be used to some extent.

These first five episodes are almost entirely about the natural world: the wildlife, the weather, the geography.

The sixth program is about how humans interact with the polar regions. Our species evolved in the Ice Age, so it is hardly surprising that we invaded the northern parts of the continents almost as soon as we could reach them. Two domesticated or semi-domesticated animals made this spread to northern climates possible: the dog and the reindeer. Early migrants and their descendants today relied heavily on the polar oceans, as agriculture of any kind is difficult in permafrost country (though I was a little surprised that permafrost was never really mentioned.) There was little mention of wild plant foods, though in fact berries and other wild plants are definitely part of the arctic diet, and the arctic in spring and summer has high productivity, as indicated by the number of migratory birds that breed at high latitudes. Today human interactions – and impacts – are more often focused on resource extraction.

Antarctica has had quite a different history. Undiscovered until relatively recently, its fauna has evolved with a lack of land predators that could make it very vulnerable. Luckily Antarctica is protected by international treaties so most of the human activity there today is scientific research. But how long will that remain true as our appetite for resources increases?

The seventh program is the “controversial” one. I’m not sure what the controversy was supposed to be about. The program shows observations at both ends of the Earth that demonstrate the thinning and melting of sea ice in the Arctic and collapse of ice sheets, which may act to buttress glaciers draining the interior, in Antarctica. The importance of enhanced glacier calving to sea level rise was touched on. The cause of this warming might be controversial, as is the use of weather records to observe it, but these were not even mentioned. Just the observed changes, and their possible impact on both the human inhabitants and the animals of the polar regions.

As an atmospheric scientist for most of my professional career, the only thing I considered even remotely controversial was the lack of any mention that human activity might in any way be responsible for the observed changes. Somehow I don’t think that was what had Discovery Channel worried.

The sun rose this morning at 4:54, and it won’t set until 10:44 this evening for 17 hours 50 minutes of daylight. We’re still gaining about 7 minutes a day. The real daylight, if you include civil twilight, is even longer – civil twilight ends after midnight, at 12:07 in the morning, and begins again at 3:27. Yes, that means it’s still pretty light at bedtime. Even at solar midnight the sky is dark blue rather than black, and the super moon Saturday night never rose above the trees to the south.

Seedlings May 6

Beans and herbs hardening off.

It’s warming fast, though nighttime frosts are still more likely than not. The beans have not only sprouted, they are growing so fast I’ve started putting them outdoors during the daytime. We’ve even had our first thunder of the season — earliest in 27 years.

#Writemotivation Check in:

1. Get the garden going. Given the earlier springs up here lately, I’ll try to get the beans started indoors by April 25 and the squash by April 30; plant outdoors before Memorial Day. Get seeds in before Memorial Day if possible. This will involve getting the hoops to support plastic covers up on all three raised beds.

Far too early to plant anything (it’s still freezing at night) but the beans are up and hardening, the squash is beginning to sprout, and I made the hoops yesterday.

2. Keep up daily blogging using my existing schedule: Alaska weather Monday, review Tuesday, quotation context Wednesday, wild card Thursday, Jarn’s Journal (back history on my sf novels) Friday, Science/technology/health Saturday, and Six Sentence Sunday Sunday. http://homecomingbook.wordpress.com/

So far so good.

3. Keep up Context? Tweets daily @sueannbowling

So far so good, also.

4. Put at least two interesting science links a day on Homecoming’s page

Almost didn’t make it yesterday, but so far I’ve kept up.

5. Get outdoors for at least a couple of hours a day when the weather cooperates, either gardening or tricycle riding.

This past week the weather hasn’t cooperated much, but I’ve done at least an hour a day (usually two) on the stationary bike and/or rowing machine.

6. Read over entire trilogy for flow; put bits on Six Sentence Sunday; find a beta reader or two if possible.

I’ve read through it once; still need a beta reader. Any takers?

The sun rose this morning at 5:19, and will not set until 10:20 this evening. We’re on daylight time, but I’m not really sure why – we certainly have no shortage of daylight! 17 hours today, and we’re gaining about 7 minutes a day. Solar altitude at noon has crossed the 40° mark, most of the snow has melted, and I’m putting the mints out to harden in the daytime. But at the darkest time of night the sun is only a little more than 10° below the horizon.

Violets and delphinium are popping up next to the south wall of the house.

The forecast is for quite a bit cooler this week, with rain and snow possible. I hope the snow doesn’t stick! I’ll probably get out the hose today, but I certainly won’t leave it hooked up at night.

I’m doing the #writemotivation check-in again this month, with a longer list of goals now OLLI is over until fall. My goals aren’t all writing this time either. Specifically:

1. Get the garden going. Given the earlier springs up here lately, the beans have started to sprout (indoors) and I’ll try to get the squash planted today if I can find pots; plant both outdoors before Memorial Day. Get seeds in before Memorial Day if possible. This will involve getting the hoops to support plastic covers up on all three raised beds.

The chives in the holes in the cement blocks making up the raised beds have reached eating height already, though we're still having hard freezes at night.

2. Keep up daily blogging using my existing schedule: Alaska weather Monday, review Tuesday, quotation context Wednesday, wild card Thursday, Jarn’s Journal (back history on my science fiction novels) Friday, Science/technology/health Saturday, and Six Sentence Sunday on Sunday. http://homecomingbook.wordpress.com/

3. Keep up Context? Tweets daily @sueannbowling

4. Put at least two interesting science links a day on Homecoming’s page: https://www.facebook.com/pages/Homecoming/109303925759274

5. Get outdoors for at least a couple of hours a day when the weather cooperates, either gardening or tricycle riding.

6. Read over entire trilogy for flow; put bits on Six Sentence Sunday; find a beta reader or two if possible. Anyone interested?

The snow is melting rapidly, the path to the shed is shoveled, and the tricycle is out – I rode about a mile yesterday. We’re forecast to have highs in the 50’s next week, though it’s still below freezing at night and could be below zero. I’m going to plant the beans (indoors) this week. Spring is coming!

It’s light almost all the time I’m awake, now – sunrise today was 5:44 in the morning, and it won’t set until 9:56 this evening for 16 hours 12 minutes of daylight, almost 7 minutes more than yesterday. The closed car now gets so hot I’ve turned on the air conditioning. We only have a couple more days of nautical night – starting April 25 the sun will never dip more than 12° below the horizon.

Pussy willows are out, and I took a few pictures from the trike. The weeds are turning green (aren’t they always the first?) and I’ve spotted new growth on delphiniums, violets, columbine, and hardy geraniums against the house even though I haven’t raked the leaf mulch out yet. Chives are showing green, too, with a nice onion flavor. It’s far too early for rototilling – there are still patches of snow in the garden, and I’m sure it’s still frozen solid, but I’ve started visiting the commercial greenhouses. Plant Kingdom had a good assortment of mints, and I bought 11, but my favorite (Corsican mint) wasn’t there. Don’t know why it’s so hard to get hold of. Maybe they’ll have it at one of the three I haven’t been to yet.

Thursday morning I happened to catch NPR’s Talk of the Nation on whether the extraordinary tornadoes this year had any link to global change. This is not a simple question, but it got me thinking about one aspect of climate change that I haven’t seen discussed much.

Weather is driven by the fact that some parts of the earth-ocean-atmosphere system receive more radiant energy than they emit to space, and other parts radiate more to space than they receive. Energy is transported from regions of excess to regions of deficit by the atmosphere and the oceans, and the result is what we call weather and ocean currents. This is one of the fundamentals of atmospheric science.

What has received less attention is that there are two types of energy imbalance that the oceans and atmosphere must balance. The first is the equator-to-pole imbalance. This is what drives ocean currents and the huge horizontal eddies that we call frontal storms and anticyclones, and the great northward and southward excursions if the jet stream. Individual years may vary greatly, both in time and in space, while the total energy transport stays about the same. A difference in the apportioning between atmosphere and ocean could make a huge difference, and this is the basis for concern that a change in the so-called conveyer belt of the oceans could be a major climatic switch.

But there is a second imbalance, and this is between the surface, which absorbs energy from the shortwave (visible) radiation of the sun, and the upper atmosphere, which radiates longwave (infrared) energy to space and back to the surface. The surface transfers energy to the air near the ground, both in the form of moisture and direct heating, and this energy must be transferred vertically to the upper atmosphere where it is radiated away—largely by water vapor, clouds, carbon dioxide and methane. Certainly some of this vertical transport is accomplished by the great horizontal eddies, via fronts—sloping surfaces where warm air moves up over cold air. But some, especially in summer, is due more directly to warm air rising with very little large-scale horizontal temperature gradient. This process produces the more violent storms—thunderstorms (which produce not only thunder but lighting, hail and tornadoes) and hurricanes.

Horizontal gradients are certainly important as feedback processes. If the Arctic sea ice continues to melt, the Arctic Ocean will absorb much more solar energy, the summer gradient of temperature will decrease, and summer storms of the large-eddy type will decrease. But the direct effect of carbon dioxide and other greenhouse gasses is to increase the vertical energy gradient, and thus the amount of energy that must be transported vertically by the atmosphere.

In current climate models this vertical energy transport is parameterized—that is, it is based on statistics taken from the present-day climate. Why? Because it happens largely through processes of cloud physics that are just too small-scale to be included directly in the models. But any time you hear climate scientists talking about a tipping point, they are really talking about a change that may change the statistics on which those parameterizations are based. If that happens, change may be much larger, and in a totally unexpected direction, than the models predict.

Could the changes be in a direction as to be opposite the prediction, so there is no real change? Possibly, just as it is possible that one storm could put things back the way they were before an earlier one struck. I am more concerned that attempts at modeling past changes we know occurred, like the glacial-interglacial transitions, generally underestimate, not overestimate, the change actually observed.

Oceanography: Exploring Earth’s Final Wilderness

It’s been almost 50 years since I took an oceanography course, so I ordered this course as a refresher. It was a refresher all right, and not just of what I remembered of oceanography — this course covers everything from the history of the Earth to modern-day pollution. As one of my old colleagues at the Geophysical Institute says, “It’s not Planet Earth, it’s planet Cloud-Ocean.”  And this course was a marvelous refresher of the whole of geophysics, core to tropopause, and some biology with the whole thing straightforward enough to be understandable to almost anyone.

It started out conventionally enough, with an overview of the history of oceanic exploration. But many of the observations of the ocean basins demanded explanation. Why did the mid-Atlantic ridge exist, for instance? The Challenger Deep? For that matter, why were island arcs so often paralleled by trenches and home to volcanoes and earthquakes? What were the magnetic stripes discovered during World War II? How was it that the sea floor, which should have been receiving sediments from the continents throughout geologic history, had astonishingly young bedrock when drills began to penetrate those sediments? Some of these questions were touched on 50 years ago, some were hastily swept under the rug, and some (such as the puzzlingly young age of the seafloor bedrock) had not even been discovered yet.

These questions eventually led to the theory of plate tectonics, and several lectures on these DVDs are devoted to explaining this theory and how it came about. But that’s a small part of the first two discs in this set of six.

The physics and chemistry of water take up several lectures. Waves, rogue waves, tsunamis, and tides are covered, along with some of the physics of water. For something so familiar (oxygen and hydrogen are two of the most common reactive elements in the universe) water has some astonishing properties. Not only does it have an extraordinarily high heat capacity and is it very nearly the universal solvent, it is one of the few compounds in which the solid phase is less dense than the liquid. In other words, ice floats! We’re so used to this we don’t even think about it, but the world would be very different if ice sank, as most solids do in their own melts.

Life in the seas is interesting in itself and also critical to feeding our global population. Food webs, plankton, jellyfish, fish, marine mammals and birds and whales all get their moments of exposure, along with fish farming.

Then the course moves on to coasts: estuaries, deltas, beaches and sea cliffs. Life is here, too, from sea grasses and mangroves to coral reefs.

The lectures then cover storms, the deep ocean circulation, and the effects of climate change and pollution.

As a meteorologist I would of course like to have seen more on the role of the oceans in influencing weather. Not only are the oceans the great flywheel of climate, and their slow response one of the problems in climate modeling, they provide much of the water vapor that transports energy around the globe. Still, 36 half hour lectures can’t cover everything. Professor Tobin certainly tried, though, and for a single course succeeded brilliantly.

All dinosaurs are bizarre, by mammalian standards. Some, however, are bizarre even to paleontologists, and the title program of this DVD is devoted to them. There is, however, a secondary program, not even mentioned on the cover, which to me was of considerably more interest.

Most of these animals are considered bizarre because they have appendages, preserved in the fossil record, that leave paleontologists wondering just why these animals have that appendage. Take the 33 foot-long Anargasaurus, for instance. Why on earth did this plant-eater have a double row of bony spines down its back? Reconstructions tend to show it with skin forming a double crest supported by those spines, but why? The only answer anyone had come up with is some kind of display crest, like the peacock’s tail.

Display organs are common, especially in today’s birds (which after all are modern dinosaurs) so I suppose it’s as good an explanation as any for such things as the plates of a Stegosaurus (which would have been potato chips to a large carnivore) or for the fanciful neck frills, often richly supplied with blood, of the Ceratopsids. Were horns used to fend off predators, of for fighting off rivals within the species? Or just for display?

In some cases the peculiarities might be associated with feeding. Take the Epidendrosaurus, for instance, a sparrow-sized dinosaur with an incredibly long third finger. Did it use its long finger as the aye-aye in Madagascar today does, to find insects in the bark of trees? Then there’s Nigersaurus, with a broad, flat head with a very wide muzzle resembling a vacuum-cleaner nozzle. Did it stand in one place and hoover up the vegetation?

This DVD is less interesting than most of the National Geographic programs scientifically, but it does show some interesting dinosaurs. If you want information on some of the animals shown, National Geographic has both an interactive site and a magazine article by John Updike.

The secondary program, which was a total surprise, should have been part of the Prehistoric Predators DVD I reviewed earlier. It was concerned with a much more recent animal, one I’d met before in Prehistoric Park—a predatory, flightless bird that could almost hold its own with sabertoothed cats and dire wolves. Certainly it seems to have taken down the same kind of prey.

These terror birds were not what you want to attract to your backyard bird feeder! Imagine an oversized ostrich with the hooked beak of a raptor, that beak (and head) enlarged to the size of a rather large war axe. With ostrich speed and taller than a man, they evolved to be the top predators on the South American continent, for many millions of years an island continent. Then a few million years ago, the isthmus of Panama joined it to North America, ending the isolation in which the terror birds had evolved. Animals crossed the new isthmus both ways. Opossums, armadillos, and porcupines moved north, but a far greater number of placental mammals moved south.

Surprisingly, a few terror birds did move north, as their fossils have been found in Florida. Did they meet with the earliest humans to colonize North America? Or were they simply unable to compete with the mega-predators already here? They did seem to survive for a long time in North America, but the jury is still out on just how long they lasted.

Tomorrow’s the day to look at quotes from Lewis Carroll, but I’ll also have a guest appearance on another blog, Christine’s Words. Stop by!

A warm January? Not in Alaska! Borrow, at the northernmost tip of the state, was only 7°F below normal, but the western and central parts of the state fared far worse: 22°F below normal at Nome, in the far west, 24°F below normal in Bethel in the southwest, a mere 14.5° below normal at Anchorage in the south, even 4°F below normal at Annette, in the far southeast.

Fairbanks, the area where I live, was 19°F below normal, for the fifth coldest January in a record that goes back over 100 years, and the coldest January since 1971. Snowfall was extremely heavy on the south coast, but lacking inland.

I remember 1971, as does anyone who lived through it. We had 100” of snowfall before the end of 1970, and the roads were well coated with ice. That was the Christmas my father visited from Kansas, and I still remember picking him up at the airport very late in the evening of December 23. The temperature was 36 above and it was raining. My father couldn’t understand why I was driving only about 5 miles an hour on a straight, level road that simply looked wet from the rain. I made sure there was no traffic in sight before I tapped the accelerator to show him why. It was a light tap, and I was able to let the fishtail correct itself, but there’s a lot of difference between wet pavement and wet ice.

By the time my father left, at the beginning of January, the temperature was 36 below and dropping fast at the start of the coldest January in the Fairbanks record. Waist-deep snow with an icy crust from the rain did not help!

But why was Alaska so cold this year when much of the rest of the country was warm?

The sun shines more directly and longer at the equator than at the poles, especially in winter. The air is radiating energy to space, so if there were no movement of air, the poles would get colder and colder while latitudes nearer the equator would get warmer and warmer. Since the earth rotates, direct flow of cold air south and warm air north forces a west-to-east current of air, the jet stream, which always has warmer air to its right side (in the northern hemisphere) and cold air to its left.

But this is an unstable situation – the cold air keeps getting colder and the warm air keeps getting warmer until the simple west to east flow breaks into waves which carry colder air south and warmer air north, though at different longitudes. In one extreme case (rare this winter) warm air from Hawaii flows north over Alaska, the so-called pineapple express, and the air turns back south over Northwestern Canada and continues south to produce the Siberian express. When this happens, temperatures in Fairbanks can be warmer than those in Miami.

The jet stream not only moves air, it steers storms. So storm tracks frequently follow the jet stream.

This January the jet stream in the western hemisphere didn’t have much in the way of waves. The cold air stayed north, while the warm air stayed south. The upper winds over Alaska mostly came from Siberia or the northernmost Pacific. Things are changing, though. Not quite as much as I might like, but probably a bit too much for those of you enjoying unseasonably balmy weather. For the jet stream forecasts, look here. The different colored lines are different forecast models. Where they cluster close together, the forecast is likely to be accurate; where they spread apart there is a lot of uncertainty. Next week? It might even warm up here, but there’s a lot of spread in the forecasts, so I’m not counting on it.

This is the first of a number of reviews of National Geographic’s DVDs on prehistoric animals, so I will start out by saying something that applies to all. They are very good in interviews with actual paleontologists. The computer graphics of the extinct animals are of moderate quality, and there are only a few clips repeated over and over again. These videos are excellent for budding paleontologists or those actually interested in the science of how we know about extinct animals, and are better than series like “Walking With Dinosaurs” in that they allow scientific arguments to be heard. They are not in the same league when it comes to the re-creation of the extinct animals.

This DVD contains two programs originally shown on the National Geographic channel: Dino Autopsy and Dino Death Trap. The first is about a rare fossilized mummy of a hadrosaur, nicknamed “Dakota,” found in the badlands of North Dakota. The fossil was found in 1999 by a teenaged paleontologist, and has supplied information on skin texture and musculature of hadrosaurs. The science is fascinating. The quality of the animation is somewhat less so.

The second program involves the excavation of a site in China. This site produced a number of near-complete skeletons from a period, the Late Jurassic, very poorly represented until now. Most of the attention is given to Guanlong, a very early form of tyrannosaurid. The skeletons are in three dimensions rather than flattened, which has been interpreted as evidence that they were trapped in soft sediments, and lie above each other in a vertical column.

There is speculation about how they died included in the video. Was a volcanic eruption to blame? Was the mud in which they were trapped due to volcanic ash falling into a marsh? Also, while these animals are the early forms of species known from the Cretaceous, the Cretaceous forms were giants, and these animals are relatively small. Guanlong’s back would about reach the waist on a standing human, yet it is an early relative of Tyrannosaurus Rex. What caused the increase in size? Did guanlong really have feathers as part of its crest? They are in the computer animation, and a relative, Dilong, is known to have had primitive feathers. The crest does appear to be a display organ (relatively thin and brittle) and feathers would have made it more conspicuous.

Overall the DVD is worth watching if you are really interested in dinosaurs. If you are looking primarily for entertainment, others are better.

The Greenhouse Carol

(To the tune of “Auld Lang Syne”)

Should present climate be forgot,
And ne’er again be seen?
Should glaciers melt and oceans rise
Just because our house is green?
Because our house is green my friends,
Because our house is green,
We’ll sit and swelter in the sun
Because our house is green.

Should deserts spread across the land
While hurricanes grow cruel
From cows and swamps and growing rice,
And from burning fossil fuel?
From burning fossil fuel, my friends,
From burning fossil fuel,
We’ll all dehydrate in the sun
From burning fossil fuel.

Should the I T C Z go away,
And the savannahs return?
Should glaciers melt and cities drown
Because the jungles burn?
Because the jungles burn, my friends,
Because the jungles burn,
We’ll parboil in the tropic sun
Because the jungles burn.

(This was actually written 22 years ago, but it’s as true as ever.)

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