Look Out! It's ALIVE!!!!

To drive around the "Big Island" of Hawaii (as I did yesterday) is to undergo go an immersion education in volcanology, climatology, geology, and biology that no classroom could ever equal. Here, you don't just read about these natural phenomena -- you experience them first-hand, through all your senses!

This is the largest, and newest of the Hawaiian Islands, and is the home of the only still-active land volcanoes in the chain, Mauna Loa and Kilauea. In fact, Kilauea is currently erupting, and has been continuously since 1983. It's considered the most active volcano in the world, for obvious reasons. Here's an aerial shot which shows the current eruption crater at Pu'u O'o. The pillar of steam and smoke in the background is rising from Halema'uma'u in the summit caldera of the mountain. Behind that appears the distinctive shield profile of the much taller Mauna Loa.

(I suspect this picture may have been uploaded backwards because it is taken looking north or northwest but the lava flow from Pu'u O'o is travelling east, not west as it appears here).

(Photo credit: USGS)

So why don’t we hear more about these eruptions? It all comes down to the simple fact that the magma feeding these volcanoes has far lower sulphur content than in many volcanic regions, and so the feeding tube to the mountain does not clog as much. Result: a Hawaiian volcano doesn’t often explode violently, hurling death and destruction for miles in every direction. More usually, in historical times, it just opens up and bleeds lava – and goes right on flowing for days, months, weeks, even years, because the lava simply can’t solidify as quickly as it could if the sulphur content were higher. Further result: Hawaiian volcanoes do not have steeply pitched cones, they form in the shape of an old warrior’s shield laid flat on the ground, face up. The picture above shows why they are called “shield volcanoes”.

The island is actually made up of no less than five of these immense mountains, and this handy graphic shows where they all sit in relation to each other:

Yes, Mauna Loa really does spread across that distance of 80 miles or so, all the way from the southwestern point to the eastern side of the island. Everything on this island is on a huge scale, and it reminds me of the Grand Canyon in that the scale is so large that the mind has trouble grasping just how much is actually being seen. The "Saddle Road" which crosses the highland plateau between Mauna Loa and Mauna Kea is an excellent example. The landscape as you drive this road changes only very slowly, but it's still more than 60 miles from one side to the other of the island. The road also reaches an altitude well over a mile above sea level (over 2 kilometres) yet you aren't really aware of it because of the long gradual slopes.  Even at that height, the 4-kilometre tall Mauna Kea (shown below) and Mauna Loa still tower far above you to their summits.

Kohala is considered extinct, and Mauna Kea is listed as dormant. Although Hualalai last erupted in the early 1800s, it has a history of erupting every 200-300 years and so is still considered at least potentially active. Mauna Loa has erupted in recent decades and is still showing definite signs of life, and Kilauea -- well, we've already explained about Kilauea.

Southeast of Kilauea, under the aquamarine Pacific, the next volcano is already working its way towards the surface.  It's already been christened "Loihi", and it's expected to break through the ocean and begin to form more dry land in anywhere from 10,000 to 100,000 years from now.  In this it's repeating a pattern that stretches back untold millennia across all the Hawaiian islands and westwards to Midway and Wake Islands -- and beyond towards Japan.

Historically Mauna Loa has usually erupted when Kilauea is sleeping, or vice versa, but this rule too has not always applied. For many years, it was believed that the smaller Kilauea was just a subsidiary part of Mauna Loa, but scientific researchers have demonstrated that Kilauea's lava has a very different chemical composition and clearly comes from a different magma chamber inside the earth.

In the west end of the Kilauea crater is the deep hole which the Hawaiians called Halema'uma'u ("House of the Great Fire"). It was believed to be the home of Pele, the volcano goddess. This reputation dates from the periods in its history when Halema'uma'u was filled by a lava lake. 

Kilauea has added many hectares of land to the island during its current eruptive phase, and the lava flows have swallowed hundreds of homes and businesses. Right now, the town of Pahoa is having its road connections to Hilo severed by the active lava flows from Pu'u O'o, and the government is rebuilding a large section of the Chain of Craters road (which was buried in the 1980s by lava from Pu'u O'o) as a means to keep Pahoa in touch with the outside world by land. In the last century, lava emitted from a crack in Mauna Loa reached almost all the way to the city of Hilo on the east coast in a matter of 4 hours -- very fast work indeed. While outsiders might consider it mere idle superstition, many residents of the Big Island still speak very respectfully indeed of Madame Pele, and no wonder!

The key attraction on the island is Hawaii Volcanoes National Park, and it's a place that should be on every person's bucket list, for my money. I know of no other place where you can learn so much, so quickly, while safely (more or less) standing atop a volcano that is actually erupting.

 Most visitors tour the Crater Rim Drive, and that's all I was able to do last time I came here. Part of it is currently closed due to eruptive activity and the consequent release of toxic sulphur fumes. The summit crater or caldera of Kilauea is a very Grand Canyon-like place, not only because of its own large size but because of the immense form of Mauna Loa completely occupying the horizon from west through north to northeast. A still photograph of the whole width of Mauna Loa from Kilauea summit is only possible by using a panoramic camera and software!

But yesterday, I drove down the Chain of Craters road, which runs from the rim of Kilauea's crater down to the southeast shore of the island, and crosses many lava flows formed during my lifetime in the process. The 2-hour drive down this road and back exposed me to an extraordinary variety of formations from the cooling process of the lava. I'd rate it as more spectacular even than the better known summit crater.

At the end of the road are the black lava cliffs where the lava flows plunged into the ocean, adding more and more land to the mass of the island.

And if this group of formations isn't already called Pele's Garden, I certainly think it ought to be!

One other fascinating sight at Kilauea is the Thurston Lava Tube. It's a natural rock tunnel formed when the lava's top surface formed a hard, dense crust but the liquid material underneath kept flowing and flowed right out, leaving the tunnel behind. I've never visited this before either.

Apologies for all the moisture in my photos, but that's another thing that happens here. The trade winds from the east blow all their oceanic moisture into the extraordinary bulk of these mountains, and the altitude causes the clouds to drop all that moisture and then disperse. The eastern side of the island is a subtropical rain forest of great density, and the western side is much more arid. Even the Kilauea crater is partly edged by rain forest on the north and east sides -- on the south and west, most vegetation is killed by the eruption fumes. The result in this case was that the summit crater was completely invisible in the mist and rain, and most of the subsidiary craters along the Chain of Craters road were also impossible to see. The famous steam vents had visibility on the rim road down to a matter of inches, and "Pele's breath" with its faint whiff of sulphur came through noticeably inside the car.

Given the weather conditions as I've explained them, it's not hard to see why all the resorts on this island are located on the west side, sheltered from the rains borne on the trade winds by the vast bulk of the volcanoes. This very site-specific climate also explains why the Kona Airport is almost all outdoors, with only shops and offices enclosed. Almost all of the Kona Coast resorts, including much of the town of Kailua and the Kona International Airport, all sit on top of lava flows from Hualalai. With the dryness, it's a startling sight indeed: a huge wilderness of contorted black rock, with tufts of yellowish grass springing up here and there. The resorts create a beautiful splash of lush green on the vast swath of black wilderness, but it's too plainly an artificial, stuck-on kind of beauty.

On this trip, as I came down from the mountains and turned north along the coast, the rain dwindled. By the time I got back to my resort, I was in blazing sunshine -- but with huge streams of dark clouds pouring out rain still sliding past just to the southwest, out of reach of the volcanoes.

A final note: the Big Island is even bigger than it seems as the volcanic terrain forces roads into some pretty twisted curves, bends and hills which slow traffic down to a crawl.  I was on the road for almost eight hours yesterday, to cover a distance about equal to the distance between Toronto and Ottawa.