Hawaii hotspot theory: the moving pencil writes...

The latest in the complex geophysics of tectonic plates and hotspots, which has direct application to the Hawaiian-Emperor chain of islands and seamounts, is that both can move.

(Image: The Hawaiian Emperor Seamount Chain, with the Hawaiian Islands at lower right and the bend clearly visible, roughly halfway to Japan. The arc at the top, where the Emperor Seamounts terminate, is the northern edge of the Pacific Plate. Credit: NOAA.)

Here's a simplified analogy.

If you repeatedly tap a pencil on a piece of paper, it makes a dot.

If you drag the paper as the pencil is tapping, it makes a line of dots.

If you start moving the pencil as the paper is being dragged, the line of dots changes direction.

There's been lots of speculation about how that works on the earth's surface. In this case, the piece of paper is the Pacific Plate—the vast chunk of the Earth's crust that underlies most of the Pacific Ocean. The pencil is a hotspot, which repeatedly pokes through the plate to form volcanoes.

Current theory is that the Pacific Plate is adrift, moving slowly to the northwest, with islands popping through as it goes over the hotspot. The nascent island Loihi and the Big Island are being formed now, fed directly by the hot spot. Maui is a million or so years old, O'ahu two or three million and Kaua'i five million years and 300 miles from the hotspot.

On it goes in roughly a straight line out to beyond Kure Atoll, where the Hawaiian archipelago takes a distinct northward turn, and it becomes the Emperor Seamounts. There's long been talk about how the change in direction took place, but most folks have settled on a change in the direction of the Pacific Plate's movement.

The newest theory is presented in Science: “The Bent Hawaiian-Emperor Hotspot Track: Inheriting the Mantle Wind,” by University of Rochester geophysicist John Tarduno, and fellow scientists Hans-Peter Bunge, Norman Sleep and Ulrich Hansen. You can find a rundown at http://www.earthmodels.org/publications/science-2009.

The upshot is that they argue that the hotspot was moving south as the Pacific Plate moved northwest, and the bend is the result of the hotspot dramatically slowing down. In the pencil-paper analogy, as the paper is being dragged by its upper left corner, the tapping pencil is being moved down, and then stops and continues tapping in place.

The science of why the hotspot moved are beyond the scope of this piece, but it's not just a theory; there is science beyind it.

One piece of compelling evidence is that geological testing can indicate how far north a volcanic rock was formed. If a hotspot were stationary, then all the rocks of the Hawaiian Emperor chain would have signs of being formed at the latitude where Loihi is now being formed.

They don't. The oldest seamounts in the Emperors were formed farther north. Tarduno, quoted in ScienceDaily, says: "The only way to account for these findings is if the hotspot itself was moving south.”

There's some background on hotspot theory at http://pubs.usgs.gov/gip/dynamic/hotspots.html.

The science paper: John Tarduno, Hans-Peter Bunge, Norm Sleep, and Ulrich Hansen. The Bent Hawaiian-Emperor Hotspot Track: Inheriting the Mantle Wind. Science, 2009; 324 (5923): 50 DOI: 10.1126/science.1161256.

© Jan TenBruggencate 2009

How many 100-mile-per-gallon car models? X-Prize says maybe 136 of them.

There might not be a big selection of cars with superb fuel economy at the local car dealer in Hawai'i, but there should be soon.

(Image: Some of the X-Prize entries are shown off. Credit: Progressive Automotive X-Prize.)

The Progressive Automotive X-Prize today announced it has an amazing 111 qualified entrants, prepared to prove they can build safe, production-capable cars that consumers will buy—and which get the equivalent of 100 miles a gallon. The builders have 136 car designs.

That's more than four times the average fuel economy of American cars.

The payoff: the winning car designer, to be selected next year, gets $10 million.

Entrants from 25 states (there is no Hawai'i entry) and 11 nations represent individuals, car makers, universities and a range of groups.

A quarter would build full-on electric cars. Nearly another quarter gasoline or diesel cars. And another quarter gas or diesel hybrids. The remaining cars include multi-fuel, natural gas, compressed air, various biofuels and variants—one is even a combined human-gas-electric powered vehicle.

In appearance, they run the gamut. There are cars that look like traditional cars, and ones that look like golf carts. Ones that look like three-wheeled motorcycles, and like high-tech plastic spiders. Some are real spacey.

And a couple look like something the kid down the street made out of junk parts.

There are two classes. For your standard suburban driver who doesn't want to stand out too much, there's the Mainstream Class: “Mainstream Class vehicles must carry four or more passengers, have four or more wheels, and offer a 200 mile range.”

For those with an edge, there's the Alternative Class: “Alternative Class vehicles must carry two or more passengers, have no constraints on the number of wheels, and allow for a 100 mile range.”

There's also a Demonstration Division that doesn't qualify for the cash prize, in which established big car makers can show off their most fuel efficient design efforts.

Says Progressive: “In the coming months, Registered Teams will undergo Design Judging based on a detailed Data Submission package, which will provide information on their vehicle's features, production capability, safety and business plans. Those that pass Design Judging will move into the performance testing phase and partake in a series of competition events that will begin as early as May 2010.”

For more information visit http://www.progressiveautoxprize.org/.

See our last post on the X-Prize here. For more RaisingIslands stories on efficient transportation, click the "efficient transportation" link in the right-hand column.

© Jan TenBruggencate 2009

Albatrosses adapted to wind, feeding conditions; at risk in changing climate

A large team of researchers has found that albatross body shape and relative wing size is linked to where they nest and how far they fly to feed.

And also, how well they may adapt to changing global climate conditions.

(Image: Albatross in flight. NOAA photo by Capt. Budd Christman, NOAA Corps.)

The team found that albatross species with smaller wings compared to their body size do not generally range as far for feeding as those with higher wing-to-body ratios—and that this may limit the ability of rare species to expand their range.

The article, “Wind, Waves, and Wing Loading; Morphological specialization may limit range expansion of endangered albatrosses,” was published in the online journal PloS ONE by Oregon State researcher Robert M. Suryan, along with a team from across the country and Japan that included David Anderson, Scott Shaffer, Daniel Roby, Yann Tremblay, Daniel Costa, Paul Sievert, Fumio Sato, Kiyoaki Ozaki, Gregory Balogh and Noboru Nakamura.

Albatrosses, of course, are famous for flapless flight. They are consummate at soaring, a flight technique that requires far less energy than wing flapping. Four of the important Pacific albatrosses are all in the genus Phoebastria.

The researchers noted that a couple of the Pacific albatross species with larger bodies, the short-tailed and waved albatrosses, have the smallest breeding ranges. They tend to breed near rich feeding waters, so the don't need to go too far.

Short-tailed albatross breed on islands in the northwest Pacific near Japan and feed in the relatively nearby rich Kuroshio and Oyashio currents. Waved albatrosses breed mostly in the Galapagos and feed in the relatively nearby Peruvian upwelling.

Of the two, the short-tailed albatross has smaller wings, but operates in an area with generally higher wind speeds, which appear to help keep it aloft. When it ventures into feeding regions with lower wind speed areas, they tend to be near the nesting area, so shorter flights can make up for the energy cost of more energetic flying.

The waved albatross has much larger wings compared to its body size, which appears linked to to low wind speeds in its feeding area.

“Waved albatrosses encounter low wind speeds year-round. Fittingly, the waved albatross had aerodynamic performances more similar to smaller albatrosses, requiring less wind to stay aloft than the short-tailed, despite being similar in body size. Hence, the waved albatross appears adapted for low wind speed and wave height environment, and, indeed, is the only albatross to breed in a tropical ocean.”

Meanwhile, albatrosses with smaller bodies and comparatively large wing surface areas, fly over much larger swaths of ocean when feeding. Satellite tag studies have found Laysan albatrosses that fly thousands of miles in a single feeding trip—going as far on a single foray as from the Northwestern Hawaiian Islands to San Francisco Bay and back.

“Smaller-bodied black-footed and Laysan albatrosses primarily nest on islands in the central North Pacific and traverse large expanses of open ocean during the breeding season to feed in the sub-Arctic transition zone and along continental shelf regions of the California and Alaska Currents,” the authors said.

Among the impacts of this study is the realization that as climate change and sea level rise threaten their current nesting islands, short-tailed albatrosses won't be able to travel long distances through low-wind areas to new nesting areas, and the waved albatrosses may not be able to traverse high-wind areas.

“Restoration of remote, predator-free, and higher elevation island habitats may be particularly important for the long-term conservation of Phoebastria species; especially islands within productive continental margins for the two endangered species that show specialization for breeding in these regions,” the authors write.

©2009 Jan TenBruggencate

Climate catastrophes loom, Hawai'i task force proposed

The pace of climate change appears to be increasing, according to several scientific reports of the last few weeks.

It now appears that there will be significant, disruptive and expensive changes to the face of the planet within the lifetimes of most people alive today.

It's a gathering storm, and most of us haven't even bothered with an umbrella.

The Hawai'i Legislature is considering mandating what appears to be a good first step in the establishment of a Climate Change Task Force: http://www.capitol.hawaii.gov/session2009/Bills/SB266_.HTM.

Senate Bill 266 would put the task force in the Department of Health, and it would be charged with the necessary but unenviable task of figuring out the impacts of climate change and sea level rise on the island's economy, infrastructure, people and natural systems.

The task force would be required to make recommendations to the Legislature and governor on preventing shoreline erosion, protecting the visitor industry, protecting and where necessary moving public infrastructure, handling health emergencies and protecting native ecosystems.

The 29-member task force will be made up of politicians and bureaucrats, representatives of industry and government, a few engineers and the military, community representatives of surfing and fishing groups, along with a single specialist in climatology or geophysics and a single environmental engineer.

It is to provide a preliminary report to next year's Legislature and a final report to the 2011 Legislature.
There are increasingly good reasons to be paying attention, and for the appointing bodies to put thoughtful representatives on this task force, presuming the Legislature passes the bill and the Governor signs it.

A couple of those reasons have been identified on RaisingIslands: http://raisingislands.blogspot.com/2009/03/rising-seas-causing-major-us-economic.html
http://raisingislands.blogspot.com/2009/03/climate-in-peril-reefs-weaken-nero.html

There are other new issues.

Increasingly, science is identifying evidence that warming is happening faster than anticipated, that seas are rising faster than previously estimated, that oceans are acidifying at alarming rates.

The British Antarctic Survey reported that thousands of square miles of ice shelf have disappeared in recent years. The Wordie Ice Shelf is entirely gone and the Larsen Ice Shelf is shrinking fast.

"The rapid retreat of glaciers there demonstrates once again the profound effects our planet is already experiencing -- more rapidly than previously known -- as a consequence of climate change," said U.S. Interior Secretary Ken Salazar.

A new estimate suggests the Arctic Ocean could be ice-free in as little as 30 years, half a century earlier than previously expected.

"In recent years, the combination of unusual warm temperatures from natural causes and the global warming signal have worked together to provide an earlier summer sea-ice loss than was predicted," said NOAA's James Overland.

The Dutch are estimating sea levels could be higher by two feet in 40 years, and others suggest several feet by the end of the century. Small island nations are begging the world to make greenhouse gas emissions cuts to slow the process.

With increasing amounts of carbon dioxide in the atmosphere turning into carbonic acid in the oceans, scientists are just beginning to tally the effects on fisheries, coral reefs and other marine ecosystems of the changing oceans.

"Ocean acidification is a serious threat to our environment and to our marine life. Changes in ocean chemistry, caused by carbon dioxide, will affect our food supply and the health of our oceans, yet research on ocean acidification is still in its infancy," said Sen. Frank R. Lautenberg (D-NJ).

"The scientific findings about climate change are frightening," said Federated States of Micronesia representative M.J. Mace, in a Reuters piece.

As researchers learn more about sea levels, one bit of information for places like Waikiki and New York (parts of Manhattan are just 5 feet above sea level) is that it's important not to focus only on the flat-water sea level.

For low-lying areas, it takes only a few inches of rise above current levels before a storm surges drive salt water into the streets, parking garages and utility conduits.

The small island nations are calling on the world to reverse the rise in greenhouse gases, so that the impacts can be reversed.

But there are still powerful forces arguing for doing nothing about the problem, other than learning to live with it.

The OPEC cartel says oil isn't the problem; it's the nations that burn it that are the problem. And besides, the world ought to keep burning oil and simply adapt to changing climate.

“OPEC considers that efforts should not be limited to mitigation, but should increasingly encompass adaptation to climate change, in particular for developing countries,” said Mohammed Barkindo, Acting for the OPEC Secretary General, in 2006, in a statement to the United Nations Climate Change Conference in Nairobi.

More recently, current OPEC Secretary General, Abdullah al-Badri, expressed similar sentiments, although he said OPEC would be willing to help fund research into carbon-capture technologies.

©2009 Jan TenBruggencate

Population crash in Hawai'i false killer whales

Researchers have identified a disturbing crash in the population of false killer whales around the Hawaiian Islands.

Recent aerial surveys, compared with surveys in 1989, suggest a significant decline in numbers of overall whales as well as in the sizes of their pods.

(Image: NOAA photo of false killer whales off Hawaii by Robin Baird.)

The most recent reports were published in the journal Pacific Science by Randall Reeves, Stephen Leatherwood and Robin Baired, under the title, “Evidence of a Possible Decline since 1989 in False Killer Whales (Pseudorca crassidens) around the Main Hawaiian Islands.”

The animals are large members of the dolphin family, and evidence suggests there is a permanent population in the waters around Hawai'i that is genetically distinct from other false killer whale populations.

The 1989 survey found massive pods—some of which had far more whales in it than the entire statewide known population today.

“Groups of more than 300 individuals were seen on three different days, with minimum counts of 380, 460, and 470 individuals in these groups.

“The encounter rate, relative species ranking, and average group size from the 1989 survey were all substantially greater than those from more recent aerial and ship-based surveys.

“The largest group observed in 1989 (470) contained almost four times as many whales as estimated for the entire main Hawaiian Islands from recent aerial surveys,” says the paper abstract.

Current population surveys suggest it's not that all whale species have declined, but that this species has suffered particularly.

“In the 1989 general surveys off the island of Hawai‘i, the false killer whale was the third most frequently sighted species of the nine documented, representing 17% of all sightings.

“In 369 days of boat-based surveys around all the main Hawaiian Islands from 2000 through 2006, undertaken throughout the year, false killer whales accounted for only 1.5% of odontocete groups sighted, and the false killer whale was the 11th most frequently encountered species of odontocete,” the paper says.

What isn't clear is why the decline has taken place—are they short of food because of increased human fishing pressure, or is it something else? That's not yet clear, the researchers say.

For more information on false killer whales, see the NOAA website, http://www.nmfs.noaa.gov/pr/species/mammals/cetaceans/falsekillerwhale.htm, or visit http://www.cascadiaresearch.org/robin/falsekillerwhale.htm.

© Jan TenBruggencate 2009