Here's a Hawaiian Mystery for You: Where Did These Circles Come From?

We were on a desolate plain on the south side of Kilauea Caldera on the Big Island exploring the ongoing volcanic activity. The smoking pit of Halemaumau Crater with her bubbling lake of molten lava was only a half mile or so north of us, so yes, we were in a closed area (but legally in this instance!).

Given that no part of the exposed Kilauea shield is older than about 1,000 years, it's almost needless to point out that this is a young geological landscape. You can see that a thick forest can be seen off in the distance, but only a few shrubs and spindly trees are present at our feet. I saw just a few bugs when I got on my hands and knees for a closer look at the gravel.

Circles occur in nature for plenty of reasons. I don't want to provide a list because this isn't a multiple-choice test: it's a thought question! Where did the circles come from?

The middle of the circles are composed of relatively uniform particles about 1-2 millimeters across. The intervening edges are made of larger unsorted fragments. As you can see in the pictures, there is sometimes a single rock in the middle of the rings, and sometimes there is a shrub.

A couple of other background information items: Kilauea is a broad shield volcano composed of thousands of basalt lava flows. It is highly active, and indeed there has been a non-stop eruption going on one place or another on Kilauea since the early 1980s, the longest sustained eruption in recorded history. The lava lake in Halemaumau has been active since 2008. One further point to consider...should we be seeing gravel here, so close to the summit of Kilauea?

So there you go: don't be afraid to speculate! Give us some ideas in the comments section...

A Flight Around the World's Highest Mountains: Mauna Kea and Mauna Loa

Mountains that make their own weather can be frustrating because...they make their own weather. High mountains in the path of consistent winds force air masses upwards, causing the water vapor within to condense, forming clouds and as often as not, rain. This is especially true around the tallest mountains on the planet.

I'm not talking about Mt. Everest in the Himalayas. It's tall of course, just over 29,000 feet above sea level. But if one measures from the base of the mountain on the sea floor, Mauna Loa and Mauna Kea on the Big Island of Hawai'i are around 32,000 feet high (Mauna Kea edges out Mauna Loa by about 120 feet). The two giants are nearly 14,000 feet above sea level, and they rise in the middle of the northeast Trade Winds of the Pacific Ocean. They are often clear for a few minutes in the early morning, but the clouds can build quickly, obscuring the view. During our field studies trip in 2016, we had been exploring for five days before the students even saw Mauna Loa at all.

I've been privileged to visit the Hawaiian Islands eight times now, and that means there've been a few chances to see the great shield volcanoes from above as I've arrived or departed from the islands, but none of them was like the scene that presented itself to me this morning. We had an early flight, and for once I was on the correct side of the plane (for the record, on flights out of Hilo you want to be on the left side of the plane). There were just a few clouds on the northeast side, but we flew through them and soon the entire north flank of Mauna Kea was spread out below.

These mountains are astoundingly big. They formed from hundreds of thousands of eruptions of non-viscous (easily flowing) streams of basaltic lava generated at a "hot spot" in the earth's mantle hundreds of miles beneath the surface. The outer lithosphere of the earth slides over the hot spot, carrying earlier-formed volcanoes to the northwest. Kauai, Maui, and Oahu were all once large shield volcanoes like Mauna Kea and Mauna Loa, but they have subsided and erosion has ripped into their flanks. Mauna Kea and Mauna Loa will eventually suffer the same fate, and in fact Mauna Kea hasn't erupted in several thousand years (a number of very expensive telescope dot its summit). Mauna Loa is still highly active, having erupted in 1984. I wouldn't be shocked if it erupted again tomorrow (which would be the karma of just having left the island).

Perhaps my favorite shot of all, the north flank of Mauna Kea

These mountains aren't just fascinating as geological entities. They are also biological refuges. There are hundreds if not thousands of rare and endemic species of plants and animals in the forests on the flanks of the mountains. There are few environments like these on the planet, a slope that climbs from beaches to tropical rainforests, temperate rainforests, high deserts, and alpine slopes. One can see from the patchwork of cleared forests on the flanks of the volcanoes that we have severely affected these unique environments in order to raise cattle and goats. Many species, especially birds, have been lost, and other are barely hanging on.

Three gigantic shields in one picture, Mauna Kea on the left, Mauna Loa in the center, and Hualapai on the right.

It was a fascinating flight around the summits of the world's highest mountains!

The Most Desolate Place in the United States? The Mauna Loa Weather Observatory

If I seem to be missing in action, it would be because I've been stuck on planes and in airports on my way to the conference and field trips of the Cordilleran Section of the Geological Society of America. Just my luck that they happen to be meeting in Hawai'i this year. I mean really, it's my luck! I am so happy to be back on the islands. We had a spare day, so we did a bit of exploring, finding our way up Saddle Road and driving to the Mauna Loa Weather Observatory, which among other things has been measuring the carbon dioxide content of our atmosphere since the 1950s.

This picture is not tilted. That's the upper slope of Mauna Loa

This post is a bit different than some. It may usually seem that I am encouraging you to visit the places that I write about, but that's not necessarily the case today. Today's destination is something you really have to want to do. Why? Because it could quite possibly be the most desolate place in the United States. It's the road reaches the 11,000 foot level of Hawaii's biggest volcano. And it's no tourist destination. There are no facilities. You can't even visit the observatory itself. It's off limits. But if you want to see a landscape that may be the closest analog on Earth to a place like Mars, this may be the place.

The road begins near the summit of Saddle Road between Mauna Loa and Mauna Kea. Most visitors head north up Mauna Kea to the Onizuka Center for Astronomical Studies. It has bathrooms, a gift shop, telescope viewing at night and grand vistas by day. It's a welcoming place. And it's only a six mile drive. If you go south towards the Observatory, the single lane road travels 17 miles, and at about the 10,000 foot level, you leave all earthly life behind (at least it is well hidden). These are lava flows, many if not most less than a century old, and what life is possible at 11,000 feet keeps getting extinguished by hot lava. It is as desolate a place as I have ever seen.

Would you want to visit this barren blasted place? Perhaps. It depends on what you want to get out of a visit to the islands. If you are in stellar shape, the road's end is a trailhead for the shortest hiking access to the top of Mauna Loa nearly 3,000 feet higher (about 3.8 miles to the summit ridge and another 3 or so to the actual summit). It's a case of instant altitude sickness just waiting to happen. If you want to see one of the most unearthly places on Earth, it may be worth your time. If you haven't seen the important parts of Hawai'i Volcanoes National Park, then your precious time might be better spent on the south side of the gigantic mountain.

Speaking for myself, I was fascinated the whole way.

The Unsung Waterfalls of Yosemite Valley

One takes their chance when deciding to visit Yosemite Valley in the springtime. The storms of winter are never quite done by then, and you may find yourself in a valley full of clouds. That's where I found myself a week back, touring the Yosemite region with my students. It had been two weeks of no precipitation, but on Saturday, the storms came back for a day.

Sentinel Falls (left) and unnamed fall (right)

So it was that we were playing hide and seek with the iconic peaks and waterfalls of Yosemite. We did get to see most of them, with Half Dome being the notable no-show. Still, clouds add a wonderful aura of mystery if they are scattered enough to reveal bits and pieces (like a feather boa dancer). It's on such days that a person can realize the full richness of waterfalls in Yosemite.

Lower Sentinel Falls

Yosemite is famous for Bridalveil Fall, Yosemite Falls, along with Nevada and Vernal Falls on the main channel of the Merced River. But in spring when the snowmelt is high or if there is heavy rain, the valley walls come alive with falling water. Sentinel Falls (above) would be world-famous were it not on the valley wall opposite Yosemite Falls, and if it didn't dry up most years before June. It falls 1,920 feet in a series of drops, of which the longest is about 500 feet. There is an equally high fall to the west.

Royal Arches Cascades

Royal Arches Cascades are on the cliffs behind the Ahwahnee Lodge (currently called the Grand Majestic or something like that). They have a total drop of about 1,250 feet. Unlike most of the others, it's not overly hard to scramble to the base of the falls in the forest east of the lodge.

Staircase Falls

A number of times I've been eating pizza at Curry Village (now called Half Dome Village because of a copyright fight), and noticed the sound of falling water. A little searching of the cliffs reveals Staircase Falls, which drop over a series of jointed ledges of granitic rock below Glacier Point. They total 1,300 feet, but like the others they are often dry by early summer.

Staircase Falls from Curry Village

There are lots of other waterfalls to discover this time of year. These are just the ones that chose to reveal themselves to us during our brief visit under the clouds. You'll be able to find plenty of others if you can get here.

I'm hard put to describe my favorite time at Yosemite Valley. Winter, for the snow and the quiet, spring for the greenery and the Dogwoods blooming and the full waterfalls, fall for the bright colors, or summer for the access. If there is a least favorite time, it's probably August when the crowds are at their greatest but the waterfalls aren't. But you know what? It's worth a visit any time you can get there.

Liveblogging the Deluge: The Other Shoe Drops!

Wait...it hasn't rained in weeks. Why am I still talking about "liveblogging the deluge"? This is the case of the other shoe dropping. For months we have had storm after storm, adding up to a record year of precipitation in Northern California, and nearly a record in the central state. The snowpack a week ago was nearly 200% of normal. So the storms have stopped, but now a tremendous amount of snow is about to melt, so we have another round of possible flooding.

This was all brought home to me this last weekend when I took my class on a field trip to Yosemite Valley. We had a short heat wave during the week prior, and the river shot above flood stage on Wednesday and stayed there until Saturday when we arrived. The valley floor was flooded in many places, and the Merced was raging downstream (below).

On Thursday, the river peaked at nearly 12 feet (9,000 cubic feet per second), and was still at 10 feet (6,500 cfs) on Saturday. With a weak storm system passing through over the weekend, the flows backed off a bit, but the next heat wave will started the cycle all over again. For perspective, the average flow at this time of year is about 2,000 cubic feet per second.

Needless to say, the waterfalls were booming. Yosemite Falls were exploding and the echoes were resounding across the valley. It sounded like boulders were falling off the cliffs.

There was a change back home, but for a different reason, I suspect. The Tuolumne River was down for the first time since early January! I took my customary walk along the Parkway River Trail in Waterford, and the water had receded some 2 or 3 feet! I checked the numbers, and indeed the flow had declined in the last week from flood stage at 11,000 cubic feet per second to about 8,500 cfs. My first thought is that the dam operators finally felt confident enough about the flood capacity at Don Pedro Reservoir, and this has to be partly true, as the lake is down to 798 feet after nearly spilling over in January at 830 feet.

A check of the flow data told a different story. For months the outflow has been at 11,000 cfs or so, and inflow at the reservoir has been around 8,000-9,000 cfs. But during the heat wave last week inflows climbed to 11,000-12,000 cfs. The releases have been fairly constant at about the same level, but now the irrigation system is starting to take a fair fraction of the river at LaGrange Dam, thus the drop in river level.

The river is still astounding. The normal channel still lies hidden beneath 10-15 feet of water, and the river is filling the flood plain in a way that hasn't been seen in decades. And it will continue, according to reports, well into the summer. Extraordinary...

The Hawai'i That Was: A Geological and Anthropological Exploration of the Islands

Since last summer I've been working on a blog series based on the geology, natural history, and anthropology of the Hawaiian Islands, loosely based on our field studies class last summer. There are a lot of stories told by these isolated islands in the middle of the Pacific Ocean. I finally reached the (possible) end of the series yesterday, and so today I'm putting together a compilation of the posts (click on the titles to get to each blog).

The Hawai'i That Was: A New Blog Series
This was the opening post that described what I hoped to do with the series. It included a picture of the Gardiner Pinnacles, the last bit of volcanic rock in the Hawaiian chain of islands. This bit of rock is the final remnant of an island that may have rivaled Kaua'i or Maui in size.

The Hawai'i That Was: To know what was we need to know Hawai'i today
I remember that the location and relative size of the islands meant little to me until I actually visited. In this post I laid out the geography of the main islands of the chain.

The Hawai'i That Was: Why Should We Care?
We are often far too ignorant of our dependence on the land and resources, and forget that they can be abused and wasted. All human societies alter the landscapes that they occupy to increase their chances for survival, and some are more successful than others. Hawai'i is a microcosm of the human experience on Earth.

The Hawai'i That Was: The Beginning of All Things, (Ba)salt of the Earth
Hawai'i begins and ends with basalt, the product of the partial melting in the mantle of the Earth. Basalt is the foundation on which the entire story of Hawai'i is written.

The Hawai'i That Was: The Abode of the Gods and Creation at Kilauea
Kilauea is the site of Hawaii's ongoing eruptive active, 33 years and counting. We saw some spectacular spattering when we visited at night. The video is in this post.

The lava lake in Kilauea Iki in 1959. We walked across it last summer

The Hawai'i That Was: Walking a Lake of Fire in "the Little Source of Great Spewing"
In 1959, a huge eruption produced gigantic columns of spewing lava and filled a depression creating a lake of fire. It's still hot today nearly 60 years later. We walked across the abyss.

The Hawai'i That Was: Pu'u O'o, the Volcano We Couldn't See
The present day lava flows at Kilauea originate at a vent called Pu'u O'o a few miles east of the summit. We didn't get to see it on this trip, but I flew right over it in 2009. Here are the pictures!

The Hawai'i That Was: Living on Uncertain Ground - The First Human Wave Arrives
Hawai'i was one of the last uninhabited places on planet Earth. We get a first look at what life was like for the earliest colonizers, and begin to understand how they changed the islands.

The Hawai'i That Was: How Can the Biggest Mountain in the World Stay So Hidden?
It was a bit strange that we were on Mauna Loa, the world's biggest mountain, and barely ever saw it. The weather on the Big Island can be fickle! No worries though, I found a lot of images in the archives.

The Hawai'i That Was: Mauna O Wakea, the Opening to the Heavens, and the Realm of Ice
There is a second gigantic volcano on the Big Island that is taller than Mauna Loa, but of somewhat less bulk. Mauna Kea is considered the realm of the gods, and in a sense modern technology reflects this as some of the world's most powerful observatories on the summit search the Universe for understanding.

The Hawai'i That Was: A Tale of Two Kipukas, and Thoughts on the Rarest Plants in the World
Ever wondered about the world's rarest plant? How about one that existed as a single specimen? That died? Someone preserved just a few seeds, so it may come back (there are about 200 planted in the kipuka today). The role of kipukas in preserving the Hawai'i that was is described in this post.

The Hawai'i That Had Never Been: A Mountain That is Younger Than Me, Mauna Ulu
An exploration of a mountain that didn't exist when I was in grade school, along with another of Hawai'i's fascinating kipukas. Mauna Ulu is a fascinating place to explore.

The Hawai'i That Was: There was a Monster in the Water at Laupahoehoe
The tragedy of the 1946 tsunami at Laupahoehoe, and how it saved hundreds of thousands in the Pacific Ocean later on, but didn't in the Indian Ocean in 2004.

The Hawai'i That Was: Where are the Rivers? Waterfalls on the Big Island
Many parts of the Big Island have no rivers despite near constant rainfall. In other places, there are some really nice waterfalls! We explore some of them in this post.

The Hawai'i That Was: A Veritable Rainbow of Sand (and cute gratuitous sea turtles)
Did you know that there are beaches in Hawai'i that are made of gemstones? Or that beaches range in color from black to white with a whole rainbow in-between? Lets explore a few.

The Hawai'i That Was: Look at the Cute Squirrel! (NOT a squirrel)
You will no doubt see a squirrel-like creature on some the Hawaiian Islands. It's not, it's a mongoose, which is an important control on pests in other lands. In Hawai'i it IS the pest. It's had a devastating affect on the native birds of the islands.

The Hawai'i That Was: Exploring Pololu Valley on an Unstable "Dead" Volcano
The Big Island is not noted for having huge coastal cliffs, but there are some nice ones on the northeast coastline. The origin of the cliff is a notable story as well, that of a gigantic prehistoric landslide.

The Hawai'i That Was: What Happened to the Stones of Pololu? A Look at Pu'ukohala Heiau
This is the story of the Pu'ukohala Heiau, one of the most intriguing archaeological sites in the Hawaiian Islands. It was built by King Kamehameha I prior to his uniting of the islands under single rule. The stones they used to build it came from the other side of the island.

The Hawai'i That Was: Lapakahi, the Kind of Place Where the Rest of Them Lived 
History seems to always be about the kings and presidents. We usually hear little about what life was like for the "commoners". Lapakahi is an archaeological site that protects a commoner's village on the northeast coast of the Big Island.

The Hawai'i That Was: Have We Got Some Real Estate for You! Exploring Kaloko-Honokohau National Historical Park
Hawai'i has a number of national parks, and one of them seems a strange choice, backed up against a Costo store near Kona. It's a barren lava flow, but treasures are hidden within its boundaries.

The Hawai'i That Was: Pu'uhonua o Honaunau, the Place of Sanctuary That Might Not Be So Safe (Geologically)
Can you ever feel safe? There are different kinds of 'safe' in Hawai'i. A few hundred years ago, small infractions could get you killed, but you could find safety and forgiveness if you could make it to a place like Pu'uhonua o Honaunau. Geologically though? Maybe not so much.

The Hawai'i That Was: Watching the Destruction of the Islands in Real Time
Flying from the Big Island to Kaua'i is like riding a time machine both backwards and forwards. We see the progression of the erosion and subsidence of the islands over the last 5 million years, but we are also seeing the future of the Big Island, five million years into the future.

The Hawai'i That Was: We Arrive on Kaua'i and Find the Beauty of Age
The Big Island and Kaua'i are separated by only a few hundred miles, but they might as well be worlds apart. They are different from each other in many ways. We begin an exploration of the oldest of the main Hawaiian Islands.

The Hawai'i That Was: History and Beauty at Ke'e Beach and the Na Pali Coast.
On the north side of Hawai'i is a spectacular coast of some of the highest beach cliffs in the world, and the remains of a hula school that operated for perhaps 800 years. Not many universities in the world can make such a claim.

The Hawai'i That Was: An Idyllic Paradise on the North Shore of Kaua'i. Sort of.
Hanalei Bay is one of the most beautiful places on planet Earth. But even paradise can be a place of danger. Why are all the houses built on stilts?

The Hawai'i That Was: Hanalei, Where the Waterfalls Seem to Stream From the Clouds
The north side of Kaua'i captures the warm moist tropical trade winds, and collects prodigious amounts of rainfall. The mountains here are the wettest places on Earth, with one spot that gets nearly 500 inches of rain per year.

The Hawai'i That Was: Rising Out of Depression on Kaua'i, and Sleeping Giants
Have you ever wondered where that unique mountain in the opening of "Raiders of the Lost Ark" was located? Actually dozens of movies have been filmed on Kaua'i somewhere. We also climb the Sleeping Giant, a slumbering hero of the native Hawaiians.

The Hawai'i That Was: Into the Last Stand of Wilderness in Kaua'i, the Alaka'i Swamp
We take a hike into the last refuge of many of the native species of the Hawaiian Islands, a high-altitude "swamp" on the Alaka'i Plateau. It is an absolutely unique environment, unlike any on Earth.

The Hawai'i That Was: What the Worst Disaster You Can Think of? The Terror of Na Pali...
The cliffs of the Na Pali is one of the most incredible shorelines in the world, and are stunningly beautiful. On the other hand, they are evidence of one of the most violent of disasters, one that was so intense that it sent waves crashing against the other islands more than a thousand feet high.

The Hawai'i That Was: The Lost Wetlands of the Mana Plain on Kaua'i
A portion of the west coast of Kaua'i exemplifies the conflict between the modern world and the natural environment that existed before. Volunteers are attempting to rebuild some of the wetlands that once existed on the Mana Plain.

The Hawai'i That Was: Waimea Canyon, the View You "Have" to Earn...
Our trip was near an end, and we took one last hike, one that end at the brink of a place so spectacular that it's been called the "Grand Canyon of the Pacific". We learned about the need to "earn" a view.

The Hawai'i That Was: The Final Refuge
For the our final blog in the series (for now at least), we have a look at Waimea Canyon, a deep gorge produced when half the island threatened to collapse and sink into the sea. We end with the realization that the natural environment that once existed in Hawai'i still survives in isolated corners here and there. These are the last refuge for many species, and many of us.

The Hawai'i That Was: The Final Refuge

Kaua'i broke, if not in half, then certainly something close to it. The entire summit of the Kaua'i volcano slipped downward along a fault four million years ago, causing streams to change their direction and causing the erosion of the spectacular gorge of Waimea Canyon. In places it is 3,000 feet deep, enough that it has been christened the "Grand Canyon of the Pacific". In our last post, we "earned" our first look at the canyon from the end of the hike at Cliff Trail Lookout.

Having read that post (okay, go back and read it!), you too have "earned" your right to enjoy the superlative views from several pull-outs from the highway leading to Koke'e Park. The class had ended and most of the students headed home, so Mrs. Geotripper and I stole away for one last visit to the canyon and the high-altitude rainforest above. It was late in the afternoon, and the sun's shadows were lengthening, bring the canyon into sharp relief. There's a story here, both in the geology, and in life. This place is a refuge.

This entire series has been an exploration of the "Hawai'i That Was", the geology, natural history, and human history of these beautiful islands in the middle of the Pacific Ocean. Over and over, we've seen examples of vast changes that have taken place in the natural landscape of the islands.

When Tahitians arrived on the islands many centuries ago, they quite probably were not the first humans. Legends have persisted of a race of magical "little" people called the Menehune. There is speculation that these people had arrived from the Marquesas Islands some time before the Tahitians, and they were driven into the hills and forests under the relentless advance of the colonizers. They eventually disappeared into dim legend. Their diminutive stature may have been a case of victors making the history by belittling the conquered.

Waimea Canyon is the setting for a more modern invasion and retreat. The arrival of first the Tahitians and then the Europeans set the stage for a devastating blow to the native flora and fauna of the islands. The colonizers brought invasive plants, rats, and disease-carrying mosquitos. They brought goats and pigs. The coastal zones were the most affected, as that is where the humans mostly settled. The birds bore the brunt of the attack. Bird malaria wiped out nearly all the native birds along the coast to the extent that settlers bemoaned the lack of bird songs. They brought birds from elsewhere for a variety of reasons, but they inevitably drove out any remaining native birds. Most visitors never see one.

The natives hang on in the highest reaches of Waimia Canyon and in the Alaka'i Plateau in the highlands above. It's too cold for the mosquitos, so malaria has not yet arrived. They've established a final refuge in the high forests like the Menehune before them. I look at the 800-foot-high Waipo'o Falls and can't help but think of the adventure stories like Lost World and King Kong.

Some of the native birds are on the verge extinction like the dozens of species already lost, but others have stable populations, at least for the time being. They face new threats, not the least of which is global warming. The new leaders inhabiting our federal government may deny it, but warming is continuing and the islands are changing. There will no doubt be changes in the frequency and intensity of storms (one rare typhoon, Iniki in 1992, actually caused the extinction of one or two species of bird). The greatest threat may be the expansion of the mosquitos into the high country refuge. There may be nothing that can be done to save the last of the natives, and they will, like the Menehune, disappear into legend.

I hope it doesn't happen. I'm driven to write on nature and environment by the hope, however tenuous, that my words and the words of many others like me, the teachers, the professors, and the researchers will break through to those who hold the power and influence. That can only really happen if the people in our society take action, much like the March for Science, and the March for Climate. A difference is being made. I've seen some isolated examples of politicians changing their critical votes because of public pressure. I hope it can continue.

In the meantime, our story has come full circle. We arrived on an island known for palm trees and coral sand beaches and Hula dances, and hopefully discovered a rich and varied ecosystem influenced by powerful geologic forces. We explored the youngest part of the islands, the newest lands, and made our way onto the oldest and most eroded island. And so we wrap it up. Look for a post very soon that will link to all of the stories in this series.

There may be an addendum before long, however. The Cordilleran Section of the Geological Society of America is meeting in Honolulu in a few weeks, and I'll be there. I'll be exploring a bit of Oahu, as well as some new sites on the Big Island. I may have some more material to add before long!

We reached the coastal plain in a brief rainstorm and were treated to a final rainbow. We headed back to the hotel and packed. We had a plane to catch in the morning.