分类必应美图下的文章

冈山沿岸的发光海洋萤火虫，日本 Bioluminescent sea fireflies along the shore of Okayama, Japan (© tdub_video/Getty Images)

Sea fireflies at the seashore

Sea fireflies may glow like the fireflies that send out backyard beacons at night, but that's about where the similarities end between the two species. Scientists call the bioluminescent crustaceans washing over these rocks Vargula hilgendorfii, and here in Japan they're commonly known as umi-hotaru. They're visible at night in the shallow sea waters and beaches of Japan, although other species of the genus Vargula can be seen glowing in the waters of the Gulf of Mexico, the Caribbean Sea, and off the California coast. Each sea firefly is about the size of a sesame seed, yet as a group they set off an impressive aura. Their glow intensifies depending on the salinity of the sea water and other physical stimuli. Besides lighting up the shores at night, the crustaceans do their part cleaning up the beach by munching on sandworms and dead fish. That's just one less thing for beachcombers to worry about during a glimmering seaside walk.

森火山国家公园中的拉森峰，加利福尼亚 Lassen Peak in Lassen Volcanic National Park, California (© Engel Ching/Shutterstock)

A peek at an explosive peak

We're looking at Lassen Peak, a volcano also known as Mount Lassen, and its reflection in Manzanita Lake. This stunning scene can be found in northern California's Lassen Volcanic National Park, which was established on this day in 1916. The volcano erupted between 1914 and 1917 (with some activity as late as 1921), but these days the surrounding area is a calm destination of trails, lakes, and stark lava beds. One of the least visited parks, Lassen was the first national park in California to fully reopen after being closed for COVID-19, although it implemented some restrictions to park services and facilities. The park also includes acres of mud pots, hot springs, steam vents, and fumaroles to remind you of the heat that's below you, including Boiling Springs Lake—one of the largest boiling lakes in the world at over 500 feet wide.

Infinity Bridge in Stockton-on-Tees, England (© Robert Smith/Alamy)

It's ∞ Day!

Gustave Flaubert wrote that 'an infinity of passion can be contained in one minute.' So, if you have boundless passion for contemplating the immeasurable, a full day should offer plenty of time. August 8 (8/8) is Infinity Day since the numeral 8 looks like a tilted ∞, the common symbol for infinity first popularized in 17th-century math books. But the concept of infinity itself represents an idea much older, inherent in the countless spiritual traditions that revere eternal gods or outline endless life cycles.

The bridge in today's image, which carries foot and bike traffic over the River Tees in North East England, wasn't designed with the infinite in mind. But denizens of Stockton-on-Tees thought the tilted figure-eight created by the reflected swooping structure was reminiscent enough of the infinity symbol that city leaders applied the name Infinity Bridge upon the bridge's 2008 completion.

鸟瞰戈梅拉岛上管风琴形状的玄武岩，西班牙加那利群岛 (© Martin Siepmann/Image BROKER/Offset by Shutterstock)

通往海滩的木板路，德国叙尔特岛 (© Kerstin Bittner/Westend61/Offset by Shutterstock)

Notojima岛附近的牡蛎养殖场，日本石川县 Oyster farm offshore from Notojima Island, Ishikawa Prefecture, Japan (© divedog/Shutterstock)

Aw shucks, It's Oyster Day

It may look like we've led you into a squishy green minefield, but don't worry, these clustered oysters will only explode with flavor. In honor of Oyster Day, August 5 of each year, we're getting a glimpse of just one method of oyster mariculture, or farming in open seawater. The briny bivalves may be grown on beds, rods, racks, or—in this case—ropes, but the basic process is simple: Growing surfaces are 'seeded' with whole or ground oyster shells before oyster larvae are introduced. The shells attract the larvae, which attach themselves and soon grow into a new layer of mature oysters. Humans have been doing this at least since the days of ancient Rome, but wild-picked oysters have been an important food source to many cultures since prehistory.

Oysters also played an important role in US history, and could impact the future of our biggest city: Until the 1800s, New York Harbor was home to a trillion or more oysters, possibly half the world's supply. Naturally growing on craggy, reeflike beds on the harbor floor, they formed strong barriers against swelling storms. By the 20th century, overharvesting and pollution had decimated New York's oyster population. When Hurricane Sandy hit the NYC region in 2012, it highlighted the city's vulnerability to extreme weather, especially as ocean levels continue to rise. Since then, initiatives have aimed to seed new beds with oyster shells, many collected from local restaurants.

图森北部托托利塔山麓上空的雷暴，亚利桑那州索诺拉沙漠 Lightning storm in the Tortolita Mountain foothills, north of Tucson, Arizona, in the Sonoran Desert (© Jack Dykinga/Minden Pictures)

The monsoon arrives in the desert

Lightning strikes are common during the summer monsoon of the American Southwest. In Arizona and New Mexico, powerful thunderstorms roll in most every afternoon from early July until mid-September. Here, in the Sonoran Desert north of Tucson, Arizona, the severe weather over the saguaro cactus makes for a dramatic scene.

The monsoon–which refers to the entire season and not just a single storm—is caused by intense daytime heat, which drives shifts in wind patterns that bring moist air to the generally arid Southwest. Mornings typically begin fair, but as temperatures rise throughout the day, precipitation gathers into clouds that finally burst in periods of heavy rain during the late afternoon and evening. The monsoon storms also bring huge dust storms called 'haboobs,' borrowing the name from similar storms in Sudan.

In Arizona, the monsoon can account for nearly half the state's annual rainfall, which averages little more than 7 inches. Water is precious in the desert, and the region relies on this weather pattern to fill reservoirs and maintain the fragile ecosystem. While dry lightning early in the season can spark wildfires, as the monsoon rain starts to fall, it helps reduce local fire danger.

Bellissima!

Isola Bella translates from Italian to English as 'Beautiful Island.' We're not going to argue with that. It certainly stands out even amid the rest of picturesque Lake Maggiore in Italy's northwestern Piedmont region. For years, the only human habitation on the island was a small fishing village. The village is still there, but in 1632, Carlo III, an Italian royal, commissioned the construction of a large palazzo (palace) on the island. The ostentatious palace includes a model Italian garden. Both are now major tourist attractions. Visitors to Stresa, the nearby town on the mainland, can book passage to Isola Bella and the other Borromean Islands for day trips or overnight stays…and our list of future travel destinations grows ever longer.

一艘游船经过时熔岩流撞击水面产生爆炸，夏威夷火山国家公园 A lava flow hits water to create an explosion as a tourist boat passes, Hawaii Volcanoes National Park (© Patrick Kelley/Getty Images)

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.

The Big Blue of the Sierras

High in the Sierra Nevada mountain range, straddling the border between Nevada and California, you'll find the largest alpine lake in North America, Lake Tahoe—sometimes called Big Blue. Seventy-two miles in circumference, with an average depth of 1,000 feet, it has the sixth-largest volume of any lake in the US—only the Great Lakes are larger. For at least 6,000 years, the territory of the Washoe people centered around Lake Tahoe, but the arrival of non-native people in the 19th century led to a series of armed conflicts and eventual loss of land to farms and townships.

The lake has a long history of disputes. Even its name wasn't formally agreed upon until 1945. Since the first European-American saw it in 1844, it has been called Lake Bonpland, Mountain Lake, Fremont's Lake, Fallen Leaf Lake, Maheon Lake, and Lake Bigler, after California's third governor and noted Confederate sympathizer, John Bigler. It was that name that Lake Tahoe finally supplanted on maps starting in 1862. But not everyone was enamored of the new moniker. Mark Twain famously criticized it as an 'unmusical cognomen' and that it should retain the name Bigler 'until some name less flat, insipid and spooney than Tahoe is invented for it.' Apparently, we're still waiting.

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