- Submerged Mountain in the Pacific
- Coming Ice Age, Global Warming, Climate Change, and Here We Go Again
- West Antarctica Sinking
- "A Lot Left to Discover"
Arctic Ice and Fashions in Fear
The Arctic ice cap didn't disappear this summer. I wasn't terribly surprised, even though last year the BBC had predicted its imminent demise. I've seen too many apocalyptic pronouncements fizzle to get excited about the latest fashions in fear.I remember when the coming ice age was supposed to doom future generations.
Later, the population explosion promised famine, war, pestilence, and finally death to all but a suffering remnant of humanity.
Instead we got disco, and dire pronouncements of the perils of global warming.
Global warming is called climate change today: and we're still presumably doomed.
Doomed, we're told, unless everybody goes back to a preindustrial way of life, joins some group, or punishes business owners. Which dubiously-effective solution is (presumably) our only hope depends on who's talking.
Some proposed actions make more sense: like developing more efficient, cleaner, technologies and wasting fewer resources.
Commies, Global Warming, and the Establishment
I remember the 'good old days,' when America's self-proclaimed best and brightest blamed communist aggression and campus radicals for whatever they didn't like. I very sincerely do not miss the 'good old days.'Today's 'establishment,' those with influence and power in America, has a different vocabulary, and they've got different ideas about what the rest of us should think. But in other ways not much has changed:
- Then
- Looking for commies
- Pursuing 'the American dream'
- Maintaining conformity
- Now
- Looking for racists
- Being afraid of
- Global warming
- Climate change
- Maintaining conformity
But sincerity doesn't guarantee accuracy. Unhappily, folks can passionately cling to ideas that make no sense. We've recently discovered physiological expanations for why emotion and reason don't play well together, and that's another topic. Topics.
Cycles
Most folks are familiar with nature's cycles: the short ones, at least.Maybe there's someone who fears that each sunset is the last we'll ever see of the sun. Most have seen the sun rise, cross the sky, set, and return the next morning so often that its return seems inevitable.
I've never heard of a 'save the moon' committee, dedicated to stopping a waning moon from disappearing. That cycle is so predictable that we've set up calendars around it.
We've been recording daily temperature changes for generations. Although each year is unique, meteorologists noticed patterns: like the average high and low for each day.
Straight Lines and Minnesota's Weather
Maybe it's this familiarity that keep someone from sounding the alarm when a nearby town's temperatures rose dramatically this March.This chart shows temperature fluctuations in Glenwood, Minnesota, in March of 2013. After a long stable period from March 6 to the 23rd, the town experienced a dramatic warming trend. By month's end it was about 15 degrees Fahrenheit warmer.
Let's forget that that I live in the northern hemisphere's temperate zone, and that Minnesota's weather is notoriously mercurial.
Drawing a straight line through the month's high temperatures, and assuming that the trend observed in March would continue, I could conclude that by the end of April we'd have highs in the 90s.
If that kept up, the thermometer would register 105 F at the end of May, 120 on June 30, and pass the boiling point in January of 2014.
(From KGHW, via Wunderground.com, used w/o permission)
That's silly. That's also one reason I don't panic when I see a straight line drawn across some bit of climate data.
1. Submerged Mountain in the Pacific
(From BBC News, used w/o permission)
"The Tamu massif is comparable in size to Olympus Mons on Mars"
" 'World's largest volcano discovered beneath Pacific"If the Tamu Massif had taken its time forming, it would probably have been a string of mountains like the Hawaiian archipelago.
BBC News (September 8, 2013)
"Scientists say that they have discovered the single largest volcano in the world, a dead colossus deep beneath the Pacific waves.
"A team writing in the journal Nature Geoscience says the 310,000 sq km (119,000 sq mi) Tamu Massif is comparable in size to Mars' vast Olympus Mons volcano - the largest in the Solar System.
"The structure topples the previous largest on Earth, Mauna Loa in Hawaii.
"The massif lies some 2km below the sea.
"It is located on an underwater plateau known as the Shatsky Rise, about 1,600km east of Japan.
"It was formed about 145 million years ago when massive lava flows erupted from the centre of the volcano to form a broad, shield-like feature...."
Earth's crust moves, but hot spots feeding volcanoes don't. Not as much, anyway. Large volcanic features, like the Hawaiian Islands or the Yellowstone Calderas, tend to form dotted lines.
(From "Windows into the Earth;" Robert B. Smith, Lee J. Siegel; used w/o permission.)
Apparently the Tamu Massif formed fast, geologically speaking, so we got one huge mountain instead of a chain.
Why Hawaii Doesn't Sink
"Largest Volcano on Earth Lurks Beneath Pacific Ocean""Lithosphere" is a fancy word for the rocky outer part of planet like ours. It's solid, but flexes. Generally you'd have to wait thousands of years to see it act elastically.
Becky Oskin, LiveScience (September 5, 2013)
"...Tamu Massif's new status as a single volcano could help constrain models of how oceanic plateaus form, Sager said. 'For anyone who wants to explain oceanic plateaus, we have new constraints,' he told LiveScience. 'They have to be able to explain this volcano forming in one spot and deliver this kind of magma supply in a short time.'...
"...Despite Tamu's huge size, the ship surveys showed little evidence the volcano's top ever poked above the sea. The world's biggest volcano has been hidden because it sits on thin oceanic crust (or lithosphere), which can't support its weight. Its top is about 6,500 feet (1,980 meters) below the ocean surface today.
" 'In the case of Shatsky Rise, it formed on virtually zero thickness lithosphere, so it's in isostatic balance,' Sager said. 'It's basically floating all the time, so the bulk of Tamu Massif is down in the mantle. The Hawaiian volcanoes erupted onto thick lithosphere, so it's like they have a raft to hold on to. They get up on top and push it down. And with Olympus Mons, it's like it formed on a two-by-four.'..."
If we think of the Hawaiian Island being on lithosphere that's like a raft, Tamu Massif is on an under-inflated air mattress.
Tamu Massif may have company. University of Houston's William Sager says that places like the Onton Java plateau, east of the Solomon Islands, might have sunken mountains, too. We don't have enough data to tell: yet.
Finally, "Tamu" sounds like it might be a name from the southwestern Pacific languages: but it's not. Dr. Sager made it up, from "Texas A & M University," where he'd taught before going to the University of Houston.
2. Coming Ice Age, Global Warming, Climate Change, and Here We Go Again
(NASA, via FoxNews.com, used w/o permission)
"Contraction: This NASA satellite image shows the ice at the smallest extent of record, with much of the Arctic Ocean uncovered.
Recovery: Contrary to predictions that the ice would have vanished by this summer, it has actually increased by 60 percent from last year."
"And now it's global COOLING! Record return of Arctic ice cap as it grows by 60% in a year"I've learned to get more information when folks give two data points, then draw conclusions from them. NASA seemed like a good place to start, since that's where Mail Online's reporter got his information.
David Rose, Mail Online (September 7, 2013)
"A chilly Arctic summer has left nearly a million more square miles of ocean covered with ice than at the same time last year – an increase of 60 per cent.
- Almost a million more square miles of ocean covered with ice than in 2012
- BBC reported in 2007 global warming would leave Arctic ice-free in summer by 2013
- Publication of UN climate change report suggesting global warming caused by humans pushed back to later this month
"The rebound from 2012's record low comes six years after the BBC reported that global warming would leave the Arctic ice-free in summer by 2013.
"Instead, days before the annual autumn re-freeze is due to begin, an unbroken ice sheet more than half the size of Europe already stretches from the Canadian islands to Russia's northern shores...."
"Downward Trend"
"Arctic Sea Ice Update: Unlikely To Break Records, But Continuing Downward Trend"The NASA press release gave one more data point. That's a bit more information to go on, but still not enough to back up the assertion that Arctic Sea Ice was going away. Not for me, anyway.
NASA press release (August 23, 2013)
"...'Even if this year ends up being the sixth- or seventh-lowest extent, what matters is that the 10 lowest extents recorded have happened during the last 10 years,' said Walt Meier, a glaciologist with NASA's Goddard Space Flight Center in Greenbelt, Md. 'The long-term trend is strongly downward.'
"The icy cover of the Arctic Ocean was measured at 2.25 million square miles (5.83 million square kilometers) on Aug. 21. For comparison, the smallest Arctic sea ice extent on record for this date, recorded in 2012, was 1.67 million square miles (4.34 million square kilometers), and the largest recorded for this date was in 1996, when ice covered 3.16 millions square miles (8.2 million square kilometers) of the Arctic Ocean...."
A few minutes later I was looking through National Snow & Ice Data Center's "Arctic Sea Ice News & Analysis" page, and found - - -
35 Years of August Ice Sheet Size
"Figure 3. Monthly August ice extent for 1979 to 2013 shows a decline of 10.6% per decade."
(National Snow & Ice Data Center, used w/o permission.)
Here, finally, I found that "downward trend" mentioned in the NASA press release. The wiggly black line showing how much ice the Arctic Ocean has had each August, is going down: on average.
My guess is that how much ice covers the Arctic Ocean in August will continue to change.
Climate Changes: So do Fashions
It's quite possible that the next third of a century will see more shrinking ice cap. Or maybe we're seeing a small part of a long cycle, and it'll start growing again.Climate cycles, other than the obvious yearly ones, seem to be out of fashion at the moment. Part of the problem seems to be that although climate has obviously changed over time, nobody's found clear-cut cyclic variations. None with the geometric beauty of a sine wave, anyway.
On the other hand, Europe's climate warmed for several centuries, cooled, and is warming again. Maybe other parts of the world, too.
Starting a thousand years ago, Europe experienced the Medieval Climatic Optimum, followed by the Little Ice Age.
It's easy to assume that when one event follows another, it was caused by the first. Sometimes that's true. Often it's not. "Post hoc ergo propter hoc" reasoning - isn't reasonable. Even though the phrase is Latin.
(From xkcd, used w/o permission.)
We're Still Learning
The end of the Little Ice Age came at roughly the same time that the industrial revolution started. Maybe coal furnaces kept Europe from freezing over. Then again, maybe not.I don't think we know enough to say exactly how Earth's climate changes on a scale of centuries, millennia, tens of thousands of years, and longer. We've only been keeping detailed records of temperature and precipitation for the last few centuries.
Our knowledge of climate before folks had thermometers, barometers, and weather satellites, comes largely from history, archeology, and paleontology.
My guess is that Earth's climate does go through long-term cycles, vaguely analogous to the short-term cycles we're more familiar with. Some of them seem to be really long, on a scale of geologic ages:
- "Earth's Interior Cycles a Contributor to Long-Term Sea-Level and Climate Change, NYU and Carleton U. Scientists Conclude"
New York University News (March 18, 2013) - "Solar Variability and Terrestrial Climate"
NASA Science News (January 8, 2013)
3. West Antarctica Sinking
(NASA, via LiveScience, used w/o permission)
"The West Antarctic Ice Sheet sits below sea level today, but 34 million years ago, it sat on a much higher mountain range."
"West Antarctic Ice Sheet's Age Gains 20 Million Years"Before discovering that West Antarctica might have been hundreds of meters higher in the past, researchers figured that the ice sheet there was about 14,000,000 years old. Now it looks like it may go back 34,000,000 years.
Laura Poppick, LiveScience (September 6, 2013)
" The West Antarctic Ice Sheet could have formed 20 million years earlier than previously thought, researchers propose, after updating a detail in global climate models, placing more confidence in those models' ability to predict future changes in global climate.
"The West Antarctic Ice Sheet accounts for only about 10 percent of the ice on the continent today. It sits below sea level and is subject to melting from warm air and seawater infiltration, more so than the larger East Antarctic Ice Sheet, which sits at a higher elevation.
"Researchers have long assumed that West Antarctica has always sat at this low elevation and has thus always been less amenable to holding ice sheets as large as those in East Antarctica...."
That won't help anybody get better mileage, whiter teeth, or lower grocery bills: but it makes a difference to folks who study Earth's climate.
4. "A Lot Left to Discover"
(From NASA IceBridge, via Yale, used w/o permission)
"NASA Data Reveals Mega-Canyon under Greenland Ice Sheet"I've said it before: the more we learn about this wonder-filled creation, the more we find that we have yet to learn. (May 3, 2013)
NASA press release (August 29, 2013)
"Data from a NASA airborne science mission reveals evidence of a large and previously unknown canyon hidden under a mile of Greenland ice.
"The canyon has the characteristics of a winding river channel and is at least 460 miles (750 kilometers) long, making it longer than the Grand Canyon. In some places, it is as deep as 2,600 feet (800 meters), on scale with segments of the Grand Canyon. This immense feature is thought to predate the ice sheet that has covered Greenland for the last few million years.
" 'One might assume that the landscape of the Earth has been fully explored and mapped,' said Jonathan Bamber, professor of physical geography at the University of Bristol in the United Kingdom, and lead author of the study. 'Our research shows there's still a lot left to discover.'..."
Related posts:
- Science
- "Oxygen, Ice, and Our Changing Earth"
(August 30, 2013) - "When the Volcano Stops Screaming - - -"
(July 19, 2013) - "Studying the Builder's Craft"
(April 5, 2013)
Particularly - "Vast and Ancient"
(February 27, 2013)
Particularly - "Climate Changes: So What Else is New?"
(May 16, 2011)
- "Oxygen, Ice, and Our Changing Earth"
- Sense
- "Getting a Grip About Politics and Principles"
(June 18, 2013) - "Sin, Outrage, and Making Sense"
(May 5, 2013) - "Population Explosion, Birth Dearth, and a Changing World"
(June 9, 2012) - "Lebanon, Israel, Pakistan, India, and the Lizard People"
Another War-on-Terror Blog (January 14, 2009)
Particularly - "Emotions, the Frontal Cortex, The War on Terror, Anarchists, and the Illuminati"
Another War-on-Terror Blog (December 23, 2008)
- "Getting a Grip About Politics and Principles"
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