40年的休养生息 40 years of recovery
Mount St. Helens National Volcanic Monument, Washington
Today is an important day in American history. We're standing on the Boundary Trail at Johnston Ridge in the Mount St. Helens National Volcanic Monument. Forty years ago today, 110,000 acres within Gifford Pinchot National Forest was set aside to memorialize the deadliest and most destructive volcanic eruption in the United States. For nearly nine hours on May 18th, 1980, the Mount St. Helens erupted, forever changing the Washington landscape. The volcanic event started at roughly 8:30 on a Sunday morning with a 5.1 magnitude earthquake. This triggered what is known as a 'lateral eruption,' which means the lava blast comes out of the side of the volcano, rather than the top. The initial blast shaved more than a thousand feet off the mountain's elevation, resulting in a massive avalanche and the destruction of about 150 square miles of the surrounding forest. When the event ended, 57 people had died, 200 homes and almost 200 miles of nearby highway had been destroyed.
The monument was established by President Ronald Reagan in 1982 to preserve the area for research, recreation, and education. The land inside has been left to mostly recover naturally since the eruption. While it's believed that Mount St. Helens will erupt again sometime within the next few centuries, that has not deterred people from hiking and climbing at the monument, which has been allowed since 1986.
世界上最活跃的火山 The most active volcano in the world
Hawai'i Volcanoes National Park at 106
The orange glow of a lava tube like the one pictured here is a frequent site on Hawaii's Kilauea, the youngest volcano on one of the youngest islands on Earth. In near constant eruption for the last 40 years, Kilauea is widely considered the most active volcano in the world and is the main attraction at Hawaii Volcanoes National Park, which was created on this day in 1916. The park, which was designated an International Biosphere Reserve and a World Heritage Site, also includes another active volcano, Mauna Loa, the world's most massive shield volcano—Mauna Loa last erupted in 1984. Together, they are among the most studied volcanoes in the world.
The volcanoes of the Big Island of Hawaii offer a real-time glimpse into the ongoing creation of the entire Hawaiian island chain, a process that has been underway for tens of millions of years. Hawaii as we know it owes its existence to a volcanic hotspot on the seafloor. Magma seeps from this hotspot and turns into solid rock. Once enough magma is extruded, the rock breaks the surface of the sea and becomes an island. The island continues to grow until the Pacific tectonic plate moves the island off the hotspot. The hotspot remains stationary, constantly creating new islands. In fact, the next Hawaiian island, named Loihi, is about 20 miles from Hawaii and 3,000 feet below the surface of the ocean. In less than 100,000 years, it is expected to replace the Big Island as the youngest island in the chain, and it too will have its turn at hosting visitors who buy timeshare condos.
Hawaiian religion credits the creation of Hawaii to Pele, the goddess of fire and volcanoes. Possessing a fiery temper and a passionate nature, she is said to make her home in the Halema'uma'u caldera here on Kilauea. From her volcano home she controls the flow of lava and frequency of eruptions. According to modern legend, she sometimes wanders near the park as an old woman wearing a red muumuu, with a white dog, as a warning that a new eruption is soon to come.
Behold the 'perfect' cone
How far would you have to travel for the 'perfect cone'? Well, probably not too far if you're talking ice cream. But if volcanoes are what you're looking for, you'll have to make your way to Mount Mayon on the Philippine island of Luzon. The glowing lava you see is on the tip of the world's most perfectly shaped, symmetrical volcanic cone, which formed after years of eruptions from what is still an active stratovolcano. Mount Mayon has erupted dozens of times in the past 400 years, and there was a significant eruption as recently as 2018. Even this year, smaller white steam plume emissions and faint crater glow are sometimes visible. Mayon is the most active volcano in an island nation full of active volcanos, and is located inside the UNESCO Albay Biosphere Reserve, as well as the Philippine's Mayon Volcano Natural Park. Despite its active status, tourists still flock to the park to view the unique beauty of this cone shaped spectacle.
When Death Valley blew its top
Deep below Death Valley's charred surface, blazing hot magma once gushed up through a geologic fault until it hit groundwater. The magma quickly turned the water to steam, and like a defective subterranean pressure cooker, the Earth's crust blew its top in a ferocious explosion. The hydrovolcanic eruption sent up a mushroom cloud of steam and spewed burnt volcanic cinders for miles. It also left the giant crater seen in this photo and 12 smaller ones spread across the surface.
The Ubehebe Crater (pronounced you-bee-HEE-bee) is a half-mile across and more than 700 feet deep. Geologically speaking, Ubehebe and the other craters here are quite young. A 2016 study concluded that the craters were all formed in a relatively brief series of explosions—a period of days or weeks—about 2,100 years ago. Another eruption could happen, but visitors need not worry about the ground below their feet—seismometers in the region will alert geologists in advance of any future volcanic unrest. A trail around the rim of the crater offers views of the colorful layers of stone along the walls. Adventurous hikers can descend to the bottom, but it's a long slog back out again, especially on a sweltering summer day.
Ubehebe火山口（发音为you bee HEE bee）宽半英里，深700多英尺。从地质学的角度来说，乌贝赫比和这里的其他陨石坑都很年轻。2016年的一项研究得出结论，这些陨石坑都是在相对短暂的一系列爆炸中形成的——大约2100年前的几天或几周时间。另一次火山喷发可能会发生，但游客不必担心脚下的地面。该地区的地震仪将在未来的火山动荡之前提醒地质学家。沿着火山口边缘的小径可以看到沿着墙壁的彩色石层。喜欢冒险的徒步旅行者可以爬到水底，但要想再次爬出来还需要很长时间，尤其是在炎热的夏天。
Are you older than this lake?
If you were born before summer 1991, the answer is yes. Sorry if you already felt a bit long in the tooth, but it's true: Before 30 years ago, Lake Pinatubo was just a rumble in Mount Pinatubo's magma-filled belly. It was a calamitous eruption on June 15, 1991—one of the 20th century's most powerful—that blew off Pinatubo's original summit and formed a vast crater, which gradually filled with water as greenery reclaimed the summit.
Located about 50 miles from the Philippines' capital of Manila, the crater was for many years a niche destination for hardy hikers, requiring days of travel to reach. More recently, a 4x4 road and tended hiking trail were added, reducing the rugged journey to a day trip.
A sizzling summit hides in the clouds
Seen here with its explosive summit socked away in the clouds, Mount Etna towers over the Italian isle of Sicily as the tallest volcano in Europe—and maybe the crankiest, given its near-constant eruptions. The island peak has been highly active for perhaps half a million years and can still be counted on for a spectacular eruption every few years. This photograph shows Etna erupting in 2013.
Fall for Chile
Autumn in Chile varies widely as one travels from the Atacama Desert in the north more than 2,600 miles south to the tip of Tierra del Fuego. Around halfway between these two extremes you can find Conguillío National Park and the volcano Llaima at Chile's center. In March, at the start of the Southern Hemisphere's autumn, the leaves of the deciduous forest begin to turn color and fall, and the native Chilean pine trees (Araucarias) stand out even more strikingly.
Because of their distinctive appearance and the fact that they thrive in a wide range of climates, the trees became a favorite of botanists in the 19th century, who transported and cultivated them in many temperate climates around the world. The 'monkey puzzle' trees got their common English name in the 1850s when English barrister Charles Austin observed that 'It would be a puzzle for a monkey to climb that.' Even more amazing is that these trees can live over a thousand years and are themselves living fossils, descended from a lineage stretching back 260 million years to the time of the dinosaurs.
A sleeping green giant
We're looking down on Chu Dang Ya, an extinct volcano that last erupted millions of years ago. Located in the Gia Lai Province in the Central Highlands of Vietnam, Chu Dang Ya, means 'wild ginger' or perhaps 'tough ginger root' in the local Jarai language. The volcano provides fertile soil for crops such as pumpkins, sweet potatoes, taro, and more. Among the best times to visit this rural gem is at the beginning of the rainy season, in late April and early May, and as the rains wind down in November. That's when Chu Dang Ya takes it up a notch—its hillsides erupt with sunflower and other wildflower blooms along roadways, dirt paths, and fields.
Where fire meets water
'Keep your distance' might be the mantra for 2020, but here at Hawaii Volcanoes National Park on the 50th state's 'Big Island,' it's always been good advice. Especially so for the passengers on this tour boat as they witness a red-hot lava flow hitting the chilly ocean with a tremendous explosion of steam.
We're visiting to mark the anniversary of the park's founding on August 1, 1916. Established some 34 years before Hawaii statehood, Hawaii Volcanoes was the first national park in a US territory. It's centered around two volcanic systems: Mauna Loa, one of the world's most massive volcanoes, and the highly active Kīlauea, which erupted continually from 1983 until an explosive 2018 eruption that calmed it for the time being.
Welcome to the Ring of Fire
Today we're visiting the pair of volcanoes known as Tolbachik—the flat-topped Plosky (Flat) Tolbachik on the left of our image, and the majestic Ostry (Sharp) Tolbachik on the right, which soars 12,080 feet above the Kamchatka Peninsula in far eastern Russia. These are just two of approximately 160 volcanoes that dot the region; 29 of them, including the Tolbachik complex, are still active. In fact, there is so much volcanic activity here that UNESCO calls the peninsula 'one of the most outstanding volcanic regions in the world,' and has designated it a World Heritage Site.
The Kamchatka Peninsula juts out from the Russian mainland between the Sea of Okhotsk to the east and the Pacific Ocean and Bering Sea to the west. The sparsely populated peninsula makes up the western edge of the Ring of Fire, a chain of volcanoes along the Pacific Ocean that account for 90% of the world's seismic activity. Wild, remote, and primal, Kamchatka is home to an abundance of wildlife: arctic fox, tundra wolves, reindeer, lynx, huge Chukotka moose, and the Kamchatka brown bear that can tip the scales at 1,400 pounds.