Monday, June 12, 2023

Why does smooth pāhoehoe lava suddenly change to crystal-filled ‘a’ā lava? A new theory.

 When water flows down a gradual stream over a generally flat bottom, it’s clear and transparent, but when it hits a steep slope like rapids and waterfalls, it turns white and frothy.

Still wet, but very different.

Similarly, newly-erupted molten volcanic rock flows smooth and sinuous as pāhoehoe lava, and then sometimes changes to an entirely different look, broken-up, chunky, rough ‘a’ā lava.

We know what’s causing the water to change—turbulence and increased speed. But what’s happening with molten rock?

A team of Stanford researchers think they have an answer. They are Cansu Culha, Sam Spinner and Jenny Suckale, and in May 2023 Geophysical Research Letters published their theory under the title, “The Yih Instability in Layered Lava Flow May Initiate the Pāhoehoe to ‘a‘ā Lava Transition.”

You find both kinds of lava at volcanoes everywhere there are basalt-erupting volcanoes, whether the Hawaiian volcanoes or those erupting through the snows of Iceland.

Most lava flows start as pāhoehoe, and then occasionally some of them suddenly change form. Instead of flowing like water down a quiet river, they change dramatically. You can even hear the change, as the ‘a’ā tinkles and pings like broken glass as it tumbles rather than flows downslope. And ‘a’ā has far more crystals in it.

The change in form, the authors write, is a big deal to volcano scientists: “These fundamental differences in flow characteristics have made understanding the transition a classic question in volcanology.”

Others have suggested that turbulence may be a factor, that if you stir up pāhoehoe, it will change to ‘a’ā. 

But how does that happen? How does smooth, internally blended lava change to rough crystalline lava?

The authors looked to the work of Chia-Shun Yih, who in 1967 wrote a seminal paper on fluid dynamics. Yih noted that when there are different viscosities in a moving liquid—meaning they flow more or less easily—that can cause instability in the fluid. That concept is now called Yih Instability.

When a lava flow starts as pāhoehoe, over time, the surface is exposed to cooler air and starts to harden. And so, soon, there is molten rock flowing at different rates of speed within the same flow.

“A key assumption in our model is that pāhoehoe flows may have internal layers,” the authors write.

And that difference between layers can cause instability, which can provoke the change from smooth lava to rough chunky lava, they propose.

But it’s complicated.

Sometimes a change in speed can prompt ‘a’ā transformation, like when pahoehoe flows over a cliff. But not always.

Sometimes just a fast-moving flow down a steep slope can prompt the change. But not always.

And sometimes, a hardened surface appears to protect the still-moving lava below from making the change. That might be what happens in a lava tube—when the surface has hardened over, and the pahoehoe lava beneath can flow long and fast without the internal viscosity layers.

With Kīlauea erupting again, the new suggestions provide volcano scientists with new ways of looking at what’s going on.

If you’re interested in a less complex review of the data than is in the Geophysical Research Letters piece, Maya Wei-Hass has a review in the journal Science, under the title “Lava comes in two flavors…”

© Jan TenBruggencate 2023

Monday, May 29, 2023

Hawai'i ocean levels inches below normal--what's going on?

 Sea levels around Hawai’i are unusually low, and have been for some months.

Experts aren’t sure why. They are pretty sure they’ll come back to normal, and higher. But because they’re not sure precisely why, they also can’t be sure when.

My canoe paddling clan in recent month has noticed that low tides have seemed really low. Like, mud flats where there’s normally water. Others may be seeing reefs where there's normally water. And seeing beaches bigger than they were last year.

To figure this out, I called Chip Fletcher, who didn’t know, but knew who would. Fletcher is the interim dean at the University of Hawai’i Mānoa School of Ocean and Earth Science and Technology. He’s the go-to guy on impacts of sea level rise in the Islands.

He suggested calling the university’s Sea Level Center, where associate director Matthew Widlandsky confirmed what we’d been seeing.

“You are right about the sea levels this year around Hawaii being lower than in recent years,” he wrote.

But while he and his colleagues have a theory about the reasons, nobody’s actually gone out and done the work to prove them. “We have not yet studied this event in detail,” Widlansky said.

One theory is that it’s associated with cooler water in the central Pacific, in connection with our just-ended three-year La Niña. Cooler water is denser, meaning it takes up less volume.

One of the several drivers of sea level rise is warmer water expanding, and this would be the reverse, a temporary situation in which cool water contracts.

But there might be more to it than just that.

We’ve experienced this kind of condition before in connection with El Niño (warm conditions) and La Niña (cooler conditions) climate cycles. A study in 2020 reviewed a 2017 period when we were having super-high tides.

Widlansky was a co-author of an article on that study, published in the Journal of Climate. Other authors were Xiaoyu Long, Fabian Schloesser, Philip R. Thompson, H. Annamalai, Mark A. Merrifield and Hyang Yoon.

“Hawaii experienced record-high sea levels during 2017, which followed the 2015 strong El Niño and coincided with weak trade winds in the tropical northeastern Pacific,” the authors wrote.

“During August 2017, the Honolulu Harbor tide gauge recorded the highest monthly average water level since records began in 1905.” That record was 17 centimeters, or more than half a foot higher than expected.

That said, high sea levels don’t always follow strong El Niño events, and didn’t after the strong 1997 event. So there’s something else also going on. Maybe winds. Maybe other stuff.

“The processes controlling whether Hawaii sea levels rise after El Niño have so far remained unknown,” they wrote.

In 2017, "the high sea levels were caused by the superposition, or stacking, of multiple contributions.”

The high sea levels associated with the 2015 strong El Niño lasted from 2016 until the end of summer in 2017, and then tapered off.

The current low water is just a couple of inches lower than normal, and it's different in different locations. 

It is not clear how long the current low stand of Hawaiian water will last. 

© Jan TenBruggencate 2023

Saturday, May 20, 2023

Gray-backed tern returns to Palmyra Atoll

 The Nature Conservancy has attracted gray-backed terns back to Palmyra Atoll after they were lost to the island, likely due to rat predation.


(Image: Gray-backed tern chick. Credit: The Nature Conservancy.)

Researchers used wooden decoys and recorded bird calls to try to convince the terns--and seven other seabird species--to land and to nest on Palmyra. A single gray-backed tern was raised on this island this season, the first in recent memory.

Gray-backed terns, formerly Sterna lunata and recently recategorized Onychoprion lunata, are pākalakala in Hawaiian. They are one of eight seabirds known to the part of the ocean that contains Palmyra, but which have not been found nesting there in recent years. They likely were preyed on and their breeding colonies removed by rats that came during World War II.

Rats were eradicated from the island in 2011. In 2020, The Nature Conservancy began trying to call the missing seabirds back to the island with loudspeakers playing recorded nesting calls, and with wooden bird decoys. These techniques have successfully called in birds in other projects.

Gray-backed terns are the first to respond.

These birds are speckled as chicks--as shown in the photo above--but as adults they have white bottomsides, gray backs, and a black head with a white stripe over the eye. 

Palmyra Atoll, roughly 900 miles south of Hawai'i, is jointly managed by The Nature Conservancy and the U.S. Fish and Wildlife Service. 

© Jan TenBruggencate 2023




 


Tuesday, March 21, 2023

I guess it's possible to be optimistic about the new IPCC report, and some are. I'm not.

The newest United Nations report on planetary climate, different from previous cautious reports, minces few words. 

Things are getting worse, and faster than ever, and we have no time left to act. Paraphrasing Yoda, it's time to do something; simply trying is not an option.

“The report is a full-throated call for the massive—yet doable—changes our species must enact to limit the damage that comes with each fraction of a degree of warming,” said Wired, the online magazine. 

There is now more carbon dioxide in the atmosphere, 410 parts per million, than in the past 2 million years—that’s before there were humans on our planet. No other period in the past 2,000 years has seen climate warming as fast as in the past 50 years.

The impacts of these changes have been seriously inequitable. The Intergovernmental Panel on Climate Change 2023 report says the people least responsible for the change are suffering the most.

“Widespread and rapid changes in the atmosphere, ocean, cryosphere and biosphere have occurred. Human-caused climate change is already affecting many weather and climate extremes in every region across the globe. This has led to widespread adverse impacts and related losses and damages to nature and people. Vulnerable communities who have historically contributed the least to current climate change are disproportionately affected,” the report said in its summary for policymakers.

You can find the actual report summary and various associated documents here

Nearly half the world’s population is vulnerable and at risk of climate change disruptions, from coastal inundation, storms, flooding, drought, food and water shortages, and related issues. That risk is playing out now, and continues to increase.

“Between 2010 and 2020, human mortality from floods, droughts and storms was 15 times higher in highly vulnerable regions, compared to regions with very low vulnerability,” the report said.

The already-observed changes include water shortages, crop failures, livestock health problems, reduced fishery yields, malnutrition, infectious diseases, community displacement, and immense impacts on ecosystems. The report cites throughout how much faith it has in its observations.

“Climate change has caused substantial damages, and increasingly irreversible losses, in terrestrial, freshwater, cryospheric, and coastal and open ocean ecosystems (high confidence). Hundreds of local losses of species have been driven by increases in the magnitude of heat extremes (high confidence) with mass mortality events recorded on land and in the ocean (very high confidence). Impacts on some ecosystems are approaching irreversibility such as the impacts of hydrological changes resulting from the retreat of glaciers, or the changes in some mountain (medium confidence) and Arctic ecosystems driven by permafrost thaw (high confidence.)”

As we move along in time, it gets worse. “Every increment of global warming will intensify multiple and concurrent hazards.”

There are two primary options: Mitigation, or doing something about it; and adaptation, or learning to live with it.

The report says we have the technology to mitigate, to turn things around. But it would take severe and dramatic action. We do not seem to be willing as a planet to do what’s necessary.

“Deep, rapid, and sustained reductions in greenhouse gas emissions would lead to a discernible slowdown in global warming within around two decades, and also to discernible changes in atmospheric composition within a few years.”

But we are not spending enough money on it, and not committing enough of our policy initiatives to it.

So what about adapting? Realistically, even with drastic action, things would get worse before the arrow of livability starts to turn upward. So some adaption will be required anyway.

Clearly the poorest among us will be hit soonest and hardest, and they will have the fewest opportunities to adapt. The wealthier communities will be able to adapt, to a degree. But increasing climate change will threaten even their adaptation options.

“Adaptation options that are feasible and effective today will become constrained and less effective with increasing global warming. With increasing global warming, losses and damages will increase and additional human and natural systems will reach adaptation limits,” the report said.

To avoid catastrophe, the report says, the world needs immediate and severe cuts in greenhouse gas emissions. To limit the worst impacts in the coming few decades, emissions need to be driven to near zero.

But policies currently in place don’t do that. If anything, they leave emissions flat, meaning the situation continues to get worse.

This is the frustration. We can do it. We must do it.  But it is not clear we will do it.

What are the odds that this particular planet can galvanize its systems to do what the IPCC says is required? Here is the IPCC’s vision:

“Effective climate action is enabled by political commitment, well-aligned multilevel governance, institutional frameworks, laws, policies and strategies and enhanced access to finance and technology. Clear goals, coordination across multiple policy domains, and inclusive governance processes facilitate effective climate action. Regulatory and economic instruments can support deep emissions reductions and climate resilience if scaled up and applied widely. Climate resilient development benefits from drawing on diverse knowledge.”

Lots of media reports—ignoring the essence of the report—are all about the upside: “We can fix this! Yes, we can!”

The Christian Science Monitor takes the middle path, noting that the IPCC “walks a fine line between desperation and hope in an effort to spur a more forceful global response.”

Some publications get lost in the weeds. CNBC decided to focus on reflecting the sun's light and heat back into space. Others wondered whether carbon capture technology is ready for prime time.  

All the while ignoring the elephant in the room--we need to stop burning oil and coal.

So, the thinking goes, maybe we can do these interesting techie things, and keep on burning coal in power plants and gasoline in our big luxury cars. And everything will be just fine.

That, of course, is dithering. And while dithering, perhaps we can ponder this: 

How much misery are we willing to subject our grandchildren and their grandchildren to, to keep living the way we are living?

© Jan TenBruggencate 2023 

Friday, March 10, 2023

Climate shifts further: La Niño is over, El Niño coming by summer

The La Nina oceanic condition, which we’ve been in for many months, has ended, and an El Nino appears likely to form in the summer or fall.

That’s the latest prediction from the Climate Prediction Center: 

It builds on the report we filed last month, when we suggested a fair chance of El Nino by mid year. That fair chance now seems to have been elevated to a pretty good chance. Spring predictions tend to be problematic, but most models see us going that way.

Thus the La Nina cool phase of Central Pacific climate is behind us, and we are in something called ENSO-neutral, ENSO being the term for the whole warm-cold cycle, El Niño Southern Oscillation.

Most climate prediction models now suggest we should shift into El Niño during the summer, and it might happen pretty quickly: “it is possible that strong warming near South America may portend a more rapid evolution toward El Niño.”

One of the things that can mean for Hawai’i is that we are likely to have a more active hurricane season. Also some other changes. More on that a little further down.

But one the questions that still challenges climate researchers is where climate change is taking the ENSO pattern broadly. There’s some suggestion that the past 40 years—since 1980—have been a little cooler than expected, a little more La Niña.

Now, many researchers say their models suggest the next few decades may swing toward more active El Niño conditions. But they don’t fully trust those models: the computer climate models of past climate don’t match up real will with actual observations of the climate. So how to be sure? A whole lot of smart people are working hard to make sense of that.  A discussion on this can be found at the ENSO blog

Among the variables: Warmer oceans can feed circulating storms, but warmer oceans and changing wind conditions can also cause changes in deep ocean upwellings. If they bring cool water to the surface from the deep ocean, then that could reduce the energy available to circulating storms like hurricanes. Changes in cloud cover could also create cooler surface conditions. And there are other variables.

“Heroic efforts are being done at modeling centers around the world to improve the representation of the physical processes,” wrote Kris Karnauskas, of the University of Colorado-Boulder.

That’s the long term.

For the coming year, what does an El Niño mean for us? There’s a nice NOAA fact sheet here. 

It suggests wetter weather at first, in late summer and fall, then drier. Maybe a dry winter this year. Weaker trade winds. More hurricanes and tropical storms. Warmer water around the Islands.

And sea levels slightly higher than normal, meaning big storm surf will reach farther inland.

All in all, interesting times.

© Jan TenBruggencate

Friday, February 24, 2023

The international enigma, a baffling sphere on Japan beach, would be no mystery to Hawai'i beachgoers

(Image: Fuji News Network image of the globally baffling sphere on Hamamatsu City beach.)


A UFO. A dragon egg. A communist plot. Another spy balloon.

Wow.

International media report they’re baffled by a mysterious metal sphere that washed up on a Japan beach.

It wouldn’t be baffling to any Hawai’i beachgoer, because we see them all the time. They wash up regularly, sometimes painted orange or yellow, but most often covered with brown-red rust. Big, hollow (or occasionally foam-filled) steel spheres used in various maritime activities.

The sphere in question, 4-5 feet in diameter, washed up on a long stretch of sand off Hamamatsu City. It caused great consternation, locally and internationally. It was isolated with yellow caution tape. Authorities subjected it to tests to determine it was empty. Eventually they hauled it off the beach and disposed of it.

And international media had fun with it. Perhaps because, after the Chinese balloon and the “pico” balloons shot down over Alaska, Canada and Lake Huron, we were primed for stories about weird round things.

The Guardian breathlessly wondered whether it was a “Spy Balloon, UFO or Dragon Ball” or maybe even a stray mine. 

Nope.

The BBC called it a “mystery sphere” and said Japan was perplexed, with some folks calling it a “Godzilla egg.” 

Oh my. But, nope.

The British media network Unilad suggested some folks thought it was a devious device sent by China or North Korea. 

Uh, uh.

The India Times reported that February 23, 2023, Japanese authorities confirmed it was “marine equipment” that had washed ashore. 

They wash up periodically on Hawaiian beaches, too. They are industrial buoys, used by maritime industries for various purposes. One popular purpose in Hawai’i is as floats for FADs or fish aggregating devices. They are also used as moorings for ships, with one end chained to an anchor and the other tied to the boat. They are sometimes used to support oceanographic monitoring equipment.

And occasionally they break free and end up as marine debris on beaches.

You can buy them

And they don’t always come as spheres

Many, like the Hamamatsu City sphere, have connection points at both ends

© Jan TenBruggencate 2023

Wednesday, February 22, 2023

Wrapping up the shot-down balloons story: Yes, balloons can crash planes

 We may not learn a whole lot more about the four objects shot down during February 2023 by American jets, other than they appeared to all be balloons carrying some sort of payload.

The first was a Chinese-owned giant balloon that drifted across North America from Alaska to North Carolina, where it was shot down February 4 after it passed the coast into the Atlantic. As best we know, it had surveillance equipment on board, multiple antennas, and presumably the capacity to track and report on U.S. communications. 

U.S. intelligence agencies tracked it from takeoff in south China, all the way to its downing off the Carolinas. We assume that we were able to gather significant intelligence from it while it operated, and more after most of it was recovered from the Atlantic. 

Three more balloons were shot down over the coastal ice in Alaska February 10, the forests of the Yukon in Canada February 11 and over the waters of Lake Huron February 12.

News reports indicate all three of them were most likely very small “pico balloons,” which are much smaller than the Chinese balloon, hard to track on radar, and which normally carry miniature payloads. One standard for these balloons is to carry transceivers that allow ham radio operators to communicate with them, or to transmit messages to them to be retransmitted to other radio operators.

None of the three small balloons was recovered, but an Illinois radio and balloon hobbyist group said the Canadian object was probably theirs.

The Northern Illinois Bottlecap Balloon Brigade said it might have been one of their mylar balloons, with the call sign K9Y0. It had been up for half a year, and had circled the globe nearly seven times. They don’t know for sure that the Yukon object, but they said it stopped transmitting about the time of the reported destruction of an object by a U.S. Fighter’s rocket. Aviation Week reported on it here. 

There may be dozens of similar balloons orbiting our planet at any time, on top of the weather balloons, corporate spy balloons, hot air balloons, party balloons, and nations’ spy balloons. In all, this Scientific American article says there may be hundreds to thousands up over the U.S. at any given time. 

Some have radio transponders so aircraft can detect them, some are reflective so they show up clearly on radar, but some are ghostly hard to detect, yet still dangerous to an aircraft that might suck one into its engine or around its control surfaces.

While plane-balloon interactions are rare, they have occurred. Most result in only minor damage to the plane, as when this Air Canada flight took out a weather balloon in 2019. https://simpleflying.com/air-canada-weather-ballon-collision.

But some have caused crashes.

Forty-five people were killed in a 1970s Russian crash after a propellor plane hit a weather balloon. 

In California in 1994, a twin-engine Piper Comanche went down, killing its pilot, after it apparently hit party balloons. 

In 2007 a Cessna lost a wing after hitting the tether line for an inflatable airship. 

And there are near misses, as when this Qatar Airlines Boeing jet managed to dodge a large balloon over Brazil last year. 

© Jan TenBruggencate 2023

Monday, February 13, 2023

Maybe alien, maybe not balloons, speculation rampant about the mysterious shot down objects

 (Image: U.S. Navy assault craft working on the recovery of debris from the Chinese balloon shot down over South Carolina February 4. Credit: U.S. Navy.)


Everything about the mystery objects we’ve been shooting down remains in limbo—partly because we and the Canadians have not completed operations to recover them.

Some American officials say it’s a step too far to suggest they are alien craft from extraterrestrial sources. Others won’t rule that out.

But we won’t have clear indications until we can actually inspect the wreckage. Until then, it’s all Area 51-type speculation.

Much of the February 4 Chinese balloon debris is still reportedly off South Carolina in 50 feet of water. The item shot down February 10 over Alaskan sea ice hasn’t been recovered because of harsh Arctic winter weather. The Royal Canadian Mounted Police are working to get at the debris of the February 11 shoot-down in wild country in the Yukon. And American forces are still trying to get at the debris of the February 12 object, which reportedly fell into Lake Huron in the American/Canadian Great Lakes.

Increasingly, descriptions of these devices are bizarre. One thing that seems clear is that they are very different. Early reports suggest they might not even all be balloons, although that’s what Senate Majority Leader Charles Schumer believes they are, according to a Los Angeles Times report.  

They are clearly different things. They fly differently. They look different.

The Chinese balloon drifted at 60,000 feet. The Alaskan and Yukon objects at 40,000 feet, and the Lake Huron object at 20,000 feet.

Descriptions vary. The Chinese balloon appeared spherical and as big as three buses. The Alaskan balloon was the size of a small car. The Yukon object was cylindrical. The Lake Huron object octagonal with strings hanging down.

In descriptions, caution has sometimes veered into the implausible, as when Gen. Glen D. VanHerck, the commander of the Air Force’s Northern Command, was asked if they might be from outside our planet. He said, “I haven’t ruled out anything at this point.” Other Administration officials said there’s no indication of anything from outside the Earth being involved.

It makes the most sense that these would all be lighter-than-air balloons of some kind, but VanHerck in a CNN story said, essentially, not so fast.

"I'm not going to categorise them as balloons. We're calling them objects for a reason… What we are seeing is very, very small objects that produce a very, very low radar cross-section," he said. 

In a CNN report, the government also expressed caution about assuming the Alaskan, Canadian and Great Lakes objects are balloons: "These objects did not closely resemble, and were much smaller than, the [4 February] balloon and we will not definitively characterise them until we can recover the debris," CNN reported, citing a White House National Security spokesperson. 

So, what? Drones? If so, how can they stay aloft for periods long enough to be drifting slowly over hours and days?

China sought to put some perspective into the discussions, saying the United States does a lot of its own balloon work. In an Associated Press article, Wang Wenbin, an official of China’s foreign ministry, said “It is also common for U.S. balloons to illegally enter the airspace of other countries… Since last year, U.S. high-altitude balloons have illegally flown over China’s airspace more than 10 times without the approval of Chinese authorities.”

That suggests the possibility that some of the high altitude objects we’re seeing could be our own vehicles, perhaps drifting post-mission.

But the one thing we know is that the Chinese balloon downed off South Carolina was Chinese, as China has confirmed that. And initial indications are that there was American technology in its electronics package. And in response to that, the U.S. has prevented six Chinese aerospace firms from using American technology without U.S. approval.

In a Washington Post report, the White House suggested China continues to downplay its own actual intrusions into the airspace of other nations.

“This is the latest example of China scrambling to do damage control. It has repeatedly and wrongly claimed the surveillance balloon it sent over the United States was a weather balloon and to this day has failed to offer any credible explanations for its intrusion into our airspace and the airspace of others,” said White House spokeswoman Adrienne Watson. 

China says its balloon was collecting atmospheric data, not spying on the land below.

And meanwhile, China was reporting that it was getting ready to shoot down some kind of flying or drifting object over its own territory. 

“Local maritime authorities in East China's Shandong Province announced on Sunday that they had spotted an unidentified flying object in waters near the coastal city of Rizhao in the province and were preparing to shoot it down, reminding fishermen to be safe via messages,” wrote Forbes, citing China’s state-controlled Global Times.


China urged its fishermen to be alert, and to take photos of any debris that lands nearby.

© Jan TenBruggencate 2023

Sunday, February 12, 2023

A fourth high altitude object shot down, this one over Lake Huron. This is just bizarre.

Is there something new and strange and scary going on in our atmosphere, or are we just hyperalert to stuff that’s been there all along?

Maybe we're now seeing it largely because we're now looking for it. And because we've only recently developed the technology to track it electronically. CNN reported that we've only been able to do do so for the past year. 

After two objects were shot down over Alaska Friday and the Yukon Saturday, the airspace over Montana was closed late Saturday due to a radar signal of something that could not be confirmed by jet, and then today, Sunday, the airspace over Lake Michigan was temporarily closed “for national security reasons.”

Then, minutes before this writing, the military shot down an object over Lake Huron. It is not clear whether that is the same object that caused the airspace closure over Lake Michigan or something else. Lake Huron is just east of Lake Michigan.

We have so little information that it’s difficult to know what to make of all this. But it’s certainly not all a bunch of weather balloons, as some have suggested. That said, it might be a whole lot of different lighter-than-air craft sent aloft by governments, corporations and even individuals.

It has been reported that the “objects” over Alaska and Canada were smaller and different from the Chinese spy balloon shot down off South Carolina a week earlier. That balloon was big and roughly spherical. The Alaskan object was much smaller, did not look like the Chinese balloon and maybe didn’t have intelligence-gathering equipment. The Canadian defense minister said the Canadian object was cylindrical, and one pilot said it had the capacity to interfere with his navigational equipment. Another pilot noticed nothing like that. 

We have no information about the object shot down over Lake Huron. 

Jets scrambled over Montana late Saturday could find nothing at the site of a “radar anomaly” that prompted a short closure of Montana airspace to civilian aircraft. As this is written, we know nothing about what prompted the Lake Michigan airspace closure today (February 12, 2023.) That airspace closure was ended after a few hours. Shortly afterward, the Lake Huron object came down.

There seem to be fleets of Chinese intelligence-gathering balloons drifting in our skies, and over the skies of dozens of nations. Four months ago, the Pentagon said, a Chinese spy balloon crashed somewhere near Hawai’i, but we don’t know whether anything was recovered from it. At the same time the Chinese balloon was drifting across America two weeks ago, another was floating over Central America.

China says they’re just weather balloons, but if so, they are big, expensive weather balloons. The one shot down two weeks ago had a massive solar panel array hanging under it. That would power a whole lot of electronics.

(I have personally recovered weather balloon electronics, which are tiny--little styrofoam boxes the size of a pocket transistor radio. That's not what was hanging from the Chinese spy balloon.)

Every major country uses weather balloons, and some—like China, the United Kingdom and the United States—use spy balloons.

And then there are also private company balloons, like the ones that raised concerns off Hawai’i a year ago, which were aeronautical balloons developed by a South Dakota firm called Raven Aerostar. They had been launched from South Dakota and had been aloft for several months. Raven Aerostar said those balloons were designed to carry electronics that could provide internet service to remote areas, could collect imagery and perform other functions.

The Raven Aerostar website provides some insight into ALL the different lighter-than-air vehicles that are available. They include Thunderhead Balloon Systems for long-duration flights. And Super Pressure Balloons for stratospheric missions. And Zero Pressure Balloons that take payloads to “the edge of space.”  And Sounding Balloons for short duration meteorological missions.

And there are Raven’s Stratospheric Airships, which look more like giant blimps than balloons. They are capable of operating at 60,000 to 70,000 feet and can stay up for months.

Those are different from dirigibles, which are maneuverable lighter-than-air craft. There are also hot air balloons, which have been a “thing” since the 1700s.

Google/Alphabet in 2021 shut down its Loon program, which proposed using balloons to provide internet service to remote areas. 

Lots of stuff drifting across the skies. As mentioned above, there is indication that the United States within the past year or so has increased its capacity to identify these low-speed, high-flying devices. That could be why we’re suddenly seeing more detections.

© Jan TenBruggencate 2023

Saturday, February 11, 2023

UFOs (now UAPs) getting shot down left and right--what the heck is going on?

The three UFOs shot down in the past couple of weeks are hardly alone—the military is reporting that UFO sightings are now running in the hundreds per year.

What the heck is going on?

We've seen strange objects off Hawai'i, and the Air Force has scrambled to check them out. There have been a couple of U.S. corporate balloons, and a Chinese balloon. So far, we haven't shot any down off Hawai'i (as far as wel know.) But policies seem to be changing, particularly when these things appear in skies occupied by passenger aircraft. 

The Chinese spy balloon we shot down two weeks ago already seems fairly mundane in view the bigger story. 

Now we've shot down an unidentified, unmanned object over northern Alaska. And today, another was shot down over the central Yukon in Canada.

The Canadian Minister of National Defense, Anita Anand, reported that the item shot down over Canada today was cylindrical in shape—that doesn’t sound like a balloon. It was flying at 40,000 feet, the same elevation as the object shot down the day before over Alaska.

This year, we have learned of hundreds more UFOs (now called UAPs) being identified over our skies, many by trained military pilots.

“Unidentified Aerial Phenomena (UAP) reporting is increasing,” said an unclassified report from the federal administration to Congress last month. The Director of National Intelligence issued the report under the title, “2022 Annual Report on Unidentified Aerial Phenomena.” 

Some of the things they’re seeing in our skies are understandable. Weather balloons and such. Some are being found in interesting places, including high security places. There is probably some bias in the data, because there would naturally be a lot more eyes in the sky in such places, but there sure seems to be something else going on, too.

Some of the objects have characteristics of spying activity: “UAP events continue to occur in restricted or sensitive airspace, highlighting possible concerns for safety of flight or adversary collection activity,” that report said.

The U.S. military is taking that seriously, having established the Department of Defense (DoD) All-Domain Anomaly Resolution Office (AARO.) Its goal—Figure out what’s going on. It will link military and intelligence branches of the U.S. government, to work together “against the UAP problem set.”

Canada’s Anand reported today that Canada plans to dramatically increase its own capacity to respond to aerial threats.

There are lots of problems with figuring out UFO/UAP identities, including distance, weather, bad lighting, and confusing sensor data. And due to such issues, some assessments are simply wrong: “a select number of UAP incidents may be attributable to sensor irregularities or variances, such as operator or equipment error.”

But not all of them. Of 366 new reports studied by AARO in less than a year, the organization preliminarily concluded that 26 were some kind of unmanned aircraft, 163 were balloons or objects like balloons (one presumes things like blimps), and six were dismissed as clutter. But that left 171 uncharacterized, and some of them had spooky behavior.

“Some of these uncharacterized UAP appear to have demonstrated unusual flight characteristics or performance capabilities, and require further analysis.”

There was one report that the Yukon UAP may have been interfering with a military jet's sensors. 

Stay tuned. Ufology is suddenly top of mind, has moved clear of the woo-woo set, and is being treated as a significant threat by the U.S as well as Canada.

© Jan TenBruggencate 2023


Have we already seen peak humpback whale populations? Maybe.

 Long-time Hawai’i residents have seen the remarkable increase in humpback whale numbers since the 1960s, but that increase could be over.

Whale numbers dropped catastrophically in the middle of the last decade, and there are suggestions that climate changes mean we may have already seen peak whale numbers. 

Although whales are impacted by lots of things, including entanglement with marine debris, swallowing marine debris, overfishing of prey resources and other issues, the key threat may be reduced food availability associated with a warming climate.

A little background.

The numbers of humpback whales got so low that the International Whaling Commission banned humpback hunting in 1966, although a couple of countries continued hunting them for several more years. They were placed on the Endangered Species List in 1970. 

In 1992, the Hawaiian Islands Humpback Whale National Marine Sanctuary was established to add protection to the Hawaiian Islands breeding grounds for the central North Pacific population of humpbacks. 

Today, there are close to 100,000 humpbacks alive globally, living in 14 identified breeding groups that do not often interbreed. At the peak population, before whaling, there may have been 125,000 to 150,000. See this source.

Around Hawai’i, at their lowest, in about 1965, there were only a few hundred animals. Hawai’i residents back then would spot an occasional spout, but nothing like the great shows of spouting and slapping and leaping that we see commonly today. Today the Hawai’i humpback whales number about 12,000 in the Islands.

The animals summer in their feeding grounds off Alaska, where they feed on the huge schools of small fish and krill, a shrimp-like creature. The whales that come to the Hawaiian Islands winter in shallow coastal waters, where they give birth, mate, and feed their young, but do not eat much. They rely on the fat stores from all that krill they have eaten during the summers up north.

But after decades of increase from their low numbers in the 1960s, the whale numbers stumbled 10 years ago, particularly from 2015 to 2016.

“Numbers then declined, including a precipitous 60% drop between 2015 and 2016,” wrote Adam Frankel, Christine Gabriele, Susanne Yin and Susan Rickards, of the Hawai’i Marine Mammal Consortium in Kamuela.

It seemed to have been linked to warming waters in the feeding grounds. An extended warm period described as “the largest marine heatwave event ever recorded in the Northeast Pacific Ocean” started in late 2013. It caused serious disruption to the ocean ecosystem. These authors didn’t know exactly how that impacted whales, but they suggested that the temperature changes impacted the food web, reducing humpback feeding success.

They are not alone. The authors of this 2022 paper said that North Pacific Heat Wave was associated with fewer surviving female whales, fewer calves, and a lower survival among those calves that were born.

“Calf survival dropped tenfold,” the authors said, and older animals also were impacted. They said “documented changes to the forage fish and zooplankton prey base” were the likely suspect.

Now, a new paper seems to confirm that hypothesis—although in the Antarctic rather than the North Pacific. It was published last month in the journal Global Change Biology, under the title “A surplus no more? Variation in krill availability impacts reproductive rates of Antarctic Baleen Whales.” 

The authors found that “krill availability is in fact limiting and affecting reproductive rates” and that humpbacks “may be at a threshold for population growth.” They said similar issues are occurring with several species of whales, as krill numbers decline in their traditional grounds, and some of them move to different parts of the sea.

That heat wave of a decade ago ended. But researchers say such heat waves have been increasing and are going to be happen more often. And that’s not good for the humpback population.

“Climatic extremes are becoming increasingly common against a background trend of global warming. In the oceans, marine heatwaves—discrete periods of anomalously warm water—have intensified and become more frequent over the past century, impacting the integrity of marine ecosystems globally,” wrote the authors of the 2023 Annual Review of Marine Science.  

These marine heat waves, the authors write, “are emerging as pervasive stressors to marine ecosystems globally.”

© Jan TenBruggencate 2023

Thursday, February 9, 2023

El Nino conditions on track to return after early summer

 There continue to be good odds that oceanic conditions will return to an El Nino state by mid-year, and that could portend a more active hurricane season for the Hawaiian Islands.

The U.S. Climate Prediction Center, in a paper issued today (February 9, 2023), said that the current La Nina is weak and continuing to weaken in the Pacific Ocean near the equator. Warmer waters are appearing in the western Pacific and moving east.

The El Nino phenomenon is often called ENSO, for El Nino Southern Oscillation. It is associated with movement of heat in ocean waters, changes in winds, alterations in rainfall patterns and much more. It seems to cycle every three to five years between El Nino, the warm phase, and La Nina, the cool phase, which we’ve been for the last couple of years.

Within a couple of months, we are expected to transition out of La Nina to ENSO neutral. That should continue until early summer. 

After that, not sure, but it’s starting to look like El Nino is in the cards, according to the latest forecast:

 “There are increasing chances of El Niño at longer forecast horizons, though uncertainty remains high because of the spring prediction barrier, which typically is associated with lower forecast accuracy.” 

Here is a National Weather Service report on the specific impacts of El Nino in Hawai’i. 

Here is the progression of the El Nino/La Nina condition, as reported on this blog: This from December 2022. And this from January 2023.

© Jan TenBruggencate

Monday, February 6, 2023

Surveillance balloons. There's THERE there, but some folks protest a little much

 Lots of drama these days about surveillance balloons after a China balloon sailed across our country and we shot it down.

And now there’s another China balloon over Latin America.

But a lot of the political furor over this is misplaced, or at least uninformed.

There’s a lot to the balloons story, and it’s an old, old tale. And to be clear, the United States has conducted balloon surveillance over both the Soviet Union and China since right after World War II. Many of those were shot down by the other guys. Here’s a technical report on that

It continues to this day, and there are lots of folks engaged in the inflatable wars.

A year ago, Hawai’i was in an uproar when a strange large balloon was spotted drifting off North Kauai, and eventually continued on to O’ahu. It was February 2022. Pacific Air Forces Public Affairs told me: "We are actively monitoring it via joint capabilities and it is under evaluation. In the event the unmanned balloon threatens the U.S. airspace or sovereignty or fails to demonstrate due regard for safety of flight, U.S. Indo-Pacific Command forces are postured to take necessary and appropriate actions in response."

It turned out it was one of two surveillance balloons developed by a company called Raven Aerostar. They had been launched from South Dakota and navigated to Hawaii by rising and falling to ride winds going in selected directions. (Which raises the interesting questions of whether, if we can control our balloons that well, the Chinese government is stretching the truth when it says it had little control over the route of its balloons.)

Raven Aerostar’s Hawai’i balloons supposedly couldn’t image the land below them, but they had others that could, and were used for surveillance and intelligence gathering by Google, NASA and the Air Force.  

But we do a lot of our own balloon work here in Hawai’i, including National Weather Service balloon launches. And big test balloons have also gone up from the Pacific Missile Range Facility at Barking Sands, Kaua’i.

Most balloon surveillance is domestic. It is governments—including ours—surveilling their own citizens or checking out the atmosphere for weather reporting, but they are also used for military purposes—and have been for more than 200 years since the French military established its air spying operations in 1794. (And the Chinese were launching flame-powered floating lanterns 2,000 years ago, but that’s a different thing.)

We launch dozens of weather balloons daily across the country. 

The U.S. Border Patrol has used blimps to keep watch on the U.S.-Mexico border. 

Israel ten years ago was using balloons—they were being called blimps—to allow police a bird’s eye view of domestic disturbances.

The Army calls its balloons system the Persistent Threat Detection System. 

China was using blimps to conduct, one presumes, spying operations in the South China Sea in 2019. 

The U.S. used lighter-than-air devices extensively in the Afghanistan war. 

Twenty years ago, Lockheed Martin had this report on balloons, which they called aerostats: “Using aerostats for surveillance purposes has a long history, from the use of hot-air balloons during the Civil War to the recent deployment of tethered air vehicles to monitor drug-running activity in the Caribbean.” 

Both the Confederate and Union armies used balloons for surveillance.

It’s not surprising that balloons are still being used in an age of satellites and drones: they’re low tech, they’re way cheaper than satellites, it doesn’t cost much if they get shot down or fail, and they stay aloft far longer than any powered aircraft that might operate at similar elevations—including drones.

So for folks with security clearances, whether in Congress or current or past administrations, to say they knew nothing about this balloon business. Well you might take that with a grain of salt. Or you might assume a little political positioning.

© Jan TenBruggencate 2023

Friday, February 3, 2023

Can sea level change promote volcanic activity in Hawai'i? This theory suggests it can.

 There’s this odd thing about Hawaiian volcanic activity—secondary volcanism.

This is the appearance of new eruptions long after the main island-building volcanic activity is done. It is also called rejuvenated volcanism.

Think Diamond Head on O’ahu, Lehua Island off Ni’ihau, and all the cinder and tuff cones around Koloa on Kaua’i, which are clearly different-looking than the landscape around them. And which date much, much younger than the lavas around them.

Why does that new lava suddenly force its ways through million-year-old rock? Traditionally, there are three theories, and rather than going through them here, you can check out Volcano Watch

Now a team of geologists from Hawai’i, Wisconsin and the United Kingdom have proposed an intriguing additional reason: dramatic sea level change.

The new report published by the Geological Society of America was written by Brian R. Jicha of the University of Wisconsin-Madison, Michael O. Garcia of the University of Hawai’i, and Charline Lormand of Durham University in the UK. It is entitled, “A possible sea-level fall trigger for the youngest rejuvenated volcanism in Hawaiʻi.”

(Citation: Jicha, Brian R., Michael O. Garcia, and Charline Lormand. "A possible sea-level fall trigger for the youngest rejuvenated volcanism in Hawaiʻi." GSA Bulletin (2023).)

Garcia makes the point that this is not an alternative but an additional theory, and that different rejuvenated volcanic activity might be associated with different mechanisms.

One of their key pieces of evidence, at volcanic hot spots around the globe, is that when sea levels have fallen significantly, geological dating shows that oceanic volcanoes have erupted in this kind of late stage volcanic activity.

During a period 350,000 years ago, sea levels dropped 300 feet below current levels—and there were corresponding eruptions on Kaua’i, Molokai and Ascension Island in the South Atlantic.

When sea levels dropped about 200 feet about 225,000 years ago, there was volcanic activity on Kaua’i.

When they dropped nearly 300 feet 150,000 years ago, volcanoes erupted on Kaua’i and in Samoa.

When they dropped 300 feet about 60,000 years ago, there were eruptions at Ascension Island, Fogo in the Cape Verde Islands, and on O’ahu. The O'ahu eruptions were at Tantalus on O’ahu and in a region called the Koko Rift.

(A caveat: Volcanoes don't always respond this way. There was another low sea level period about 25,000 years ago, when Fogo, Samoa and Tristan de Cunha in the South Atlantic erupted, but Hawaiian volcanoes apparently didn’t engage in rejuvenated volcanism. And there was an unusual Kaua’i eruption about 320,000 years ago when sea levels were comparatively high, which doesn’t follow the trend.)

This kind of volcanic activity seems less likely to occur when sea levels are high. But they do when it’s low. The theory is that lower sea levels create stresses in the earth’s crust, and those let the magma force its way into dikes and sometimes to the surface. 

“Numerical modeling indicates that when sea level falls 40 m (40 meters, or about 120 feet) below the present-day level, the induced tensile stresses trigger dike injections. If sea level continues to fall to -70 or -90 m (210-270 feet) the induced tensile stress is inferred to allow dikes to reach the surface and erupt,” the researchers wrote.

They did extensive work on the Koko Rift, an 18-kilometer line of volcanic activity that runs an axis from Koko Head and Koko Crater across the Ko’olau ridge to Kāohikaipu Island off Makapu’u. All the several volcanoes along that line erupted about the same time, roughly 67,000 years ago: “The Koko Rift eruptions are analytically indistinguishable in age,” they wrote.

The Koko Rift volcanics are also the most recent examples of secondary or rejuvenated volcanism in Hawai’i—younger than the cinder or tuff cones elsewhere on O’ahu or on the other islands.

There have been other suggested explanations for secondary volcanic activity, but this one seems to be a good fit.

“Oscillations in sea level were recently recognized as a potential key mechanism for modulating volcanism by causing crustal stress from loading and unloading in ocean regions,” they wrote.

The low sea level periods are associated with ice ages—periods when vast amounts of the planet’s water is locked up in ice caps, glaciers and snow fields.

Certainly, sea levels aren’t the only cause of eruptions, and as mentioned earlier, there are cases of rejuvenated volcanism outside low stands of the sea. 

And there is certainly plenty of eruptive activity during high sea level periods now, including the ongoing Kīlauea eruption, the recent Mauna Loa eruption, historic eruptions at Kama’ehuakanaloa (formerly Lō’ihi), Hualālai and Haleakalā, and a possible 1956 eruption in the Ka’ie’ie Channel between Kaua’i and O’ahu.

The authors of the rejuvenated volcanism paper concluded: “Future investigations of rejuvenated volcanism in Hawai‘i and globally should also consider the long-term influence of the Earth’s climate system on magmatic processes to better infer past and future eruptive behavior.”

It is also true that advances in science are driving new revelations, Garcia said in an email: "We are continuing to better understand secondary volcanism with an ongoing study of the age and geochemistry of Honolulu lavas. One might think that after more than 100 years of studying these lavas that we would fully understand them but new, more precise analytical methods are allowing us to gain a better understanding."

© Jan TenBruggencate 2023

 

Thursday, February 2, 2023

Plastic pollution is inescapable, and it contributed to the death of our sperm whale

 


(Images--above and at bottom--of marine debris from sperm whale belly, courtesy UH Health and Stranding Lab.)

If you’re a fish or a turtle or most any kind of marine life feeding in the Pacific, it’s hard to avoid the plastic.

Almost all of the sea’s creatures end up ingesting some of it, and that includes the massive (56 feet, 50ish tons) sperm whale that washed up at Lydgate Park last week.

The Ocean Cleanup estimates 5 trillion bits of plastic in the ocean. 

And 1.8 trillion bits in the Great Pacific Garbage Patch, that vast gyre that runs roughly between Hawai’i and the Aleutians and California. 

The World Economic Forum estimates the ocean has 75 to 199 million tons of plastic. 

So if a critter opens its mouth to take a bite of food, it’s hard to miss getting some plastic as well.

And they do.

There are microplastics in squid

Plastics in all species of marine turtles

Plastics in tuna, including canned tuna meat

Plastics in many kinds of seabirds

The Maritime Aquarium in Connecticut estimates that by 2050, the way we’re going, there will be more plastic in the ocean than fish.  

So, no surprise when an adult sperm whale washed ashore dead last week, it had a bellyful. Of plastic.

“A major finding was the number of manufactured items in the whale’s stomach,” said Dr. Kristi West, director of the University of Hawaiʻi at Mānoa Health and Stranding Lab. It could have been enough plastic to cause a blockage, and could have contributed to the whale’s death, West said.

In addition to squid beaks and fish skeletons and other natural food remains, they found chunks of plastic netting, plastic bags, bits of rope, monofilament fishing line, a fishing net float, and several of the odd cone-shaped black plastic devices that are the doors to hagfish traps.

This is shocking, but it isn’t news. Whales of many species, including sperm whales, have been stranding all around the world with plastic in their guts. And the filter-feeding Humpback whales that seasonally slap and leap around Hawai'i are not exempt, although they tend to ingest tinier bits of plastic. 

The study into the cause of the Lydgate  whale’s death will continue with laboratory analysis of organ and other body parts, and it may be a long time before a firm cause of its demise is established, if it is.

And as for the plastics, where does it all come from? Certainly a lot from fishing operations—some of the ropes, and monofilament, and nets, and hagfish traps and plastic floats. But it’s estimated far more comes from the land—blowing off the shore, sluicing down storm drains and, the biggest source, washing down big rivers.

© Jan TenBruggencate 2023

 





Tuesday, January 31, 2023

Using mirrors to convince birds to nest: experiments at Lehua Island


(Image: Aerial view of Lehua Island, courtesy of DLNR.)

 If you’re lonely, does looking in a mirror help? Probably not, but it may help for seabirds.

One of the tools wildlife biologists use for re-establishing colonies of some seabirds is mirror boxes—structures with multiple mirrors, designed to convince the birds that there are more of them than there really are.

That’s being attempted at Lehua Island, a small tuff cone island off Ni’ihau, where biologists are trying to re-establish several bird species that once nested there.

Those efforts have a chance of working, since rats were declared eradicated from the island in 2021. Rats are believed to have caused the failure of several nesting species on the island, since the rodents eat both eggs and young birds.

Rat predation is significant: “rats (particularly black rats; Rattus rattus) are considered to be a direct cause of the threatened status of at least 75 island-nesting species of seabirds,” wrote the authors of this paper. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0076138

But once the rats are gone, there is the question of how to convince birds to start nesting in a location again. Mirrors are a solution for some bird species.

The mirror technique is not new, and it seems to work. Researchers in California, who were trying to re-establish a colony of common murre found that once they arrived, the birds were far more dense around mirrors than in other parts of the colony. They seem to like being in crowds. 

At Lehua, mirror boxes are one of the techniques being used to try to lure three species of terns back to Lehua: the ʻewaʻewa or Sooty Tern,  pākalakala or Gray-backed Tern, and the hinaokū or Blue-gray Noddy. 

In addition to the mirror boxes, there are speakers broadcasting recordings of tern songs, and decoy birds.

The state Department of Land and Natural Resources reported on the efforts in this press release.

Researchers are using different techniques to try to attract endangered ‘akē’akē or Band-rumped Storm-petrel and ʻuaʻu or Hawaiian petrels to Lehua. For those species artificial nest boxes and recorded bird calls are believed to be more effective.

All these birds are believed to be normally flying in Hawaiian waters, but several may be nesting in colornies on Kaua’I, Ni’ihau and elsewhere that are at risk from predation. Lehua is free of rats, cats, pigs, dogs and most other predators, so it is considered a good spot for colony re-estalbishment.

But it is not entirely predator-free. Researchers in 2019 published a paper that reported introduced barn owls are preying on seabirds there and elsewhere. 

Authors Andre Raine, Megan Vynne and Scott Driskill reported on the impacts of barn owls at nesting sites on Kaua’i, Lehua and at the small island Moku’ae’ae off Kīlauea Point.

The owls, which ironically were introduced to Hawai’i for the purpose of controlling rats, tend to take adult nesting birds of numerous species.

“Owl depredations were recorded of eight seabird species, the most common of which were Wedge-tailed Shearwater Ardenna pacifica, Black Noddy Anous minutus, and Bulwer’s Petrel Bulweria bulwerii. Included were 21 depredations on federally listed Newell’s Shearwater Puffinus newelli and Hawaiian Petrel Pterodroma sandwichensis,” they wrote.

While rats generally went after eggs and young, owls generally take adult birds.

Their recommended solution:: “Barn Owl control should be considered as an integral part of all Hawaiian seabird management programs.”

© Jan TenBruggencate 2023

Sunday, January 29, 2023

Why did the sperm whale die? That's not yet clear, but myriad possibilities

 It will likely be weeks or longer before we know why a big sperm whale washed ashore on Kauai, or we may never know.

Some folks have already been suggesting theories, but without doing the science, it’s guesswork.

There are many known causes of sperm whale strandings—many natural and some involving human activities.

Veterinarians and other wildlife experts are doing the hard work to conduct a necropsy on the more than 50-foot sperm whale that washed up at Lydgate Beach Park in Wailua, Kaua’i, on the morning of January 28.

But let’s look at some of the possibilities.

Whales do get old and die. They get viruses and other diseases. They can be affected by parasites. There is some evidence that climate change can impact navigation and food availability. They can be injured by natural (think big sharks) or human (think container ship impacts) causes. Noise can disorient them, and that noise can be from natural causes like undersea earthquakes, or human causes like deep sea mining exploration, sonar and noisy big ships.

The options really are too numerous for guesses to be taken seriously. Some recent strandings have had various causes.

One sperm whale that beached in the Florida Keys last year was very thin. On investigation, it had ingested marine debris, which had interfered with its ability to feed.

A 30-foot sperm whale that washed up this month in Oregon had injuries consistent with being hit by a ship.

This 2018 study suggests that some North Sea strandings may simply have been because the healthy but young sperm whales inadvertently swam into shallow water and couldn’t get back into the deep. 

Sperm whales, like many others, can become engangled in marine debris like ropes and buoys, and can be weakened by having to drag all that weight. Entanglement in fishing gear like buoys can make it difficult for whales to submerge for feeding.

This 2005 study and this 2009 study suggested that sunspot activity and even changes in the Earth’s magnetic field could impact sperm whale stranding. 

As we reported recently at Raising Islands, roughly half of recent stranded whales of various were associated with a newly described virus. 

In some cases, there are multiple things going on, such as skin disease, liver disease, parasites, viral infections, bacterial infections, fungal infections, high concentrations in blubber of man-made chemicals like pesticides and PCBs, and having ingested plastic while feeding. In many cases, it is not possible to determine which, if any, of these was the cause of the stranding.

And then there is the whole issue of climate change, which can impact marine life in numerous ways, including forcing animals into unfamiliar feeding territories, impacting feeding for juvenile animals, and much more. This Australian study from 2013 suggested: “Reductions in the extent of key habitats, changes in breeding success, a greater incidence of strandings in dugongs and cetaceans, and increased exposure of coastal species to pollutants and pathogens are likely.” 

In one month last year, 17 whales of several different species stranded off Norway. The cause is not known, and as the authors of this paper wrote, “Whale strandings are common globally, although to date there are still many challenges in identifying their cause.” 

© Jan TenBruggencate 2023

Saturday, January 28, 2023

Sperm whale strands on Kaua'i's Lydgate Beach at Wailua

 


An adult sperm whale washed ashore early today (Saturday, January 28, 2023) at Lydgate Park in Wailua, on Kaua’i.

The county issued a press release urging people to stay away from the popular beach park while government agencies respond to the incident.

The marine mammal appeared by initial estimates to be more than 50 feet in length, and could weigh 30-45 tons.

The whale was reported visible on the reef off the beach park Friday afternoon, apparently already dead. By morning it was washing in the shorebreak. Government officials were working to determine how to deal with the animal.

Sometimes dead marine mammals are brought ashore for burial. Sometimes they are towed out to sea. And occasionally, particularly when they are in remote locations, they are left to decompose in place, where they become a major food resource for crabs and other coastal marine life.

However, Kaua’i County’s Lydgate Beach Park is hardly a remote location. It gets hundreds of visitors daily for its white sand beach, protected swimming area, pavilions, playground, tennis courts and more. The whale carcass was roughly in the middle of the beach fronting the park, about 1,500 feet south of the mouth of Wailua River.

No cause of death has been determined, but National Oceanic and Atmospheric Administration personnel, along with state Department of Land and Natural Resources personnel, will conduct a necropsy to gather evidence.

In a 2017 stranding of five pilot whales at Kalapaki Beach, about six miles south of Lydgate, the animals were removed to a remote island location, where necropsies were conducted before burial of the whales.

Sperm whales are found regularly in the deep waters off the Hawaiian Islands and the rest of the Pacific, and they were a key target of the whaling fleets that operated around the Islands during the early 1800s. There have been sperm whale strandings on several Hawaiian Islands.

In December 2021, an adult sperm whale washed ashore at Pila’a, Kaua’i, about a dozen miles north of Wailua.

Whale strandings and deaths have been linked to disease, parasites, impact injuries from watercraft and other causes, but the cause of many strandings is never determined.

Newsweek earlier this month reported an unusual increase in marine mammal strandings recently, including two sperm whales and seven humpbacks in the North Atlantic since December. 

NOAA Fisheries reports that on average, there are 20 strandings of whales or dolphins in the Hawaiian Islands in any given year. 

Just this week, researchers at the University of Hawai’i and NOAA reported on a newly discovered virus that was found in the tissues of 15 of 30 tested cetaceans that died on beaches in Hawai’i, Samoa, Saipan and at sea. It is not clear that virus was the cause of death in any of these cases, but it has the capacity to cause significant illness in some dolphins and whales. We reported on that in an earlier blog. 

Sperm whales are the largest of the toothed whales, with adults ranging from 40 to 52 feet in length. The Lydgate whale appears to be at the upper end of that range. They can range in weight from 15 to 45 tons, according to NOAA Fisheries.

They are found throughout the world’s oceans, and while their population has increased significantly from the heavy whaling years, they continue to be listed as endangered under the U.S. Endangered Species Act and depleted under the Marine Mammal Protection Act. They are now protected throughout their range.

NOAA estimates that more than 400,000 sperm whales were taken between the start of whaling in 1800 and its end in 1987 in the North Pacific alone, and more in other oceans. 

A study reported last year in Nature estimates that the pre-whaling global population of sperm whales approached 2 million, that it was severely depleted by whaling, and that in 2022, the number had grown back to around 850,000. But the study said those estimates are very uncertain.

© Jan TenBruggencate 2023

Thursday, January 26, 2023

New clues in Hawai'i whale strandings

 


Whale and dolphin strandings are generally fatal to the marine mammals involved, but also traumatize their human cousins who attend them.

Often, researchers have been unable to figure out why the animals appear to commit suicide. Now there’s a hint of a clue.

Two of the pilot whales that stranded (image above) on Kaua’i’s Kalapaki Beach in 2017 suffered from a newly discovered virus that affected multiple organs.

It was October 13, when five pilot whales drove themselves onto the sand at the popular beach outside Lihue, and fronting what is now the Sonesta Kauai resort. People tried pushing the whales back into the sea, but often they swam or washed right back in. More whales from the same pod were herded away from the beach by paddlers and surfers, and appeared to have survived and left the bay.

They were short-finned pilot whales, Globicephala macrorhyncus.

 A new study of necropsy samples from numerous whale and dolphin strandings—on Kaua’i, O’ahu, Molokai, Maui, Hawai’i Island, as well as Saipan and American Samoa—shows that those two Kaua’I animals and many of the other stranded cetaceans were suffering from a newly discovered beaked whale circovirus.

The study was published today (Jan. 26, 2023) in the journal Frontiers in Marine Research. Its authors are Cody Clifton and Kristi West of the University of Hawai’i College of Tropical Agriculture and Human Resources and the university’s Hawai’i Institute of Marine Biology; Ilse Silva-Krott of Hawai’i Institute of Marine Biology; and Michael Marsik of the National Marine Fisheries Service in Pago Pago.

They call the virus an “emergent disease with unknown population impacts.”

The researchers studied archived tissues collected in necropsies of 30 individuals involved in recent Pacific strandings—including from the brain, kidney, liver, lung, spleen and lymph nodes. In many cases, the virus—identified through PCR testing—was found in multiple organs.

The tissues were being stored at the University of Hawai‘i Health and Stranding Laboratory.

“Of the screened individuals, 15 animals tested positive in one or more tissues, with a single striped dolphin (Stenella coeruleoalba) testing positive in all six tissues,” they wrote.

“Brain tissue was the most consistently positive tissue type (69%), followed by lymph tissue (67%) and lung tissue (64%),” they wrote.

It is not clear whether the viral infection caused or was directly related to the strandings, but it is a significant medical issue for marine mammals.

“Infectious diseases pose a major threat to cetaceans and (beaked whale circovirus) may represent an important emerging disease within populations spanning the central, Western, and South Pacific,” the authors wrote.

Different circoviruses are known from pets and wild animals, including birds, and while they may cause minimal health effects, they can sometimes be fatal. They can be associated with tissue inflammation as well a tissue death in organs. They are often associated with difficulty breathing.

And yet, sometimes, animals can be profoundly infected without showing significant symptoms. A false killer whale accidentally caught at sea had the virus in its brain, lungs, liver and lymph nodes, and yet appeared perfectly healthy.

The earliest recognized occurrence of this virus was in a Longman’s beaked whale (Indopacetus pacificus) that stranded on Maui in 2010. The presence of this particular virus was not identified until 10 years after its death. That one was a very sick whale. It was infected with multiple viruses. The authors of the study said multiple infections like this are not uncommon.

And although that Longman’s Beaked whale gave the virus its name, the disease has now been found in 10 other species of marine mammal. And the authors fully expect it to be found in more marine mammals.

A press release on the study is here. 

© Jan TenBruggencate 2023