夏天去过旧金山，尤其是黄昏到过金门大桥的人，应该见识过旧金山的海雾。学过海洋气象的我，偶尔也会润色几篇关于青岛海雾的文章。但是，下面这篇文章让我第一次知道海雾对人类生存的重要性。

The Elusive Future of San Francisco’s Fog

难以捉摸的旧金山海雾的未来

John Branch, a Times reporter based in the Bay Area, and photographer Nina Riggio spent months chasing fog in and around San Francisco. Scott Reinhard, a Times graphics editor, worked with researchers to visualize decades of fog data.

Sept. 14, 2022

 （原文发表在NYT） 

SAN FRANCISCO — It was the first morning of summer, the start of fog season. But the sky above the Golden Gate Bridge remained clear and blue.

Chris Dzierman, a bridge painter and foreman, looked to the west. Near the horizon, where water usually meets sky, a thick fog bank lurked. He wondered if and when it would roll in, as fog usually does on summer afternoons, smothering the bridge and beyond in wind and whiteness.

旧金山——那是夏天的第一个早晨，雾季的开始。但金门大桥上方的天空依然清澈湛蓝。
金门大桥油漆工兼工头克里斯·齐尔曼（Chris Dzierman）向西看去。在地平线附近，通常是水与天空相遇的地方，潜伏着厚厚的雾堤。他想知道雾是否会涌进来，以及什么时候会涌进来，就像夏天午后的雾通常会涌进来那样，让桥梁和更远的东部消失在风和白色中。

“It could last three minutes or three hours,” Mr. Dzierman said. “It’s fog. It’s got a mind of its own.”

“它可能持续三分钟或三小时，”齐尔曼先生说。 “雾，有它自己的打算。”

Every summer, fog breathes life into the Bay Area. But people who pay attention to its finer points, from scientists to sailors, city residents to real estate agents, gardeners to bridge painters, debate whether there is less fog than there used to be, as both science and general sentiment suggest.

每年夏天，雾都会为湾区注入活力。但是，从科学家到水手，从城市居民到房地产经纪人，从园丁到大桥油漆工，关注其细节的人们争论着雾是否比过去少了，正如科学和一般认知感觉的那样。

The ecological, economic and social effects of fog are profound, perhaps no more than in Northern California. Changes would be life-altering. But understanding fog is one of science’s toughest tricks. Quantifying the changes and determining possible causes, including global warming, is climatology’s version of chasing ghosts.

雾的生态、经济和社会影响是深远的，可能不只限于北加州。雾的变化将改变当地的生活和生态。但了解雾（的未来变化）是科学中最难的问题之一。量化雾的变化并确定造成这种变化的可能原因（包括全球变暖），就像“在捉鬼”一样。

That day on the bridge, computer models predicted the fog would push through the Golden Gate in an hour or two. Mr. Dzierman trusts his gut. He had a hunch it would stay away, defying the familiar summertime cycle.

那天的计算机模型预测雾将在1～2个小时内穿过金门。 Dzierman 先生更相信自己的直觉。他有一种预感，雾不会东进，它会偏离人们熟悉的夏季雾的周期。

Just then, a slight breeze, an invisible puff of chill, the kind you might get by opening the freezer door.

就在这时，一阵微风，一股无形的寒意，像你打开冰箱冷冻柜门时可能会感受到的那种凉意。

“Feel that?” he said, inhaling deeply. “Mother Nature’s air-conditioning. Yeah, that feels good.”

“感觉到了吗？”他说，深深地吸了口气。 “大自然的空调。是的，感觉超好。”

It was a tease.

可惜，只是挑逗而已。

The day remained gloriously sunny, unusually hot and fog-free, the kind of San Francisco summer’s day that some fear is becoming more frequent. The bridge’s five fog horns went unused, for now.

那一天，始终阳光明媚，异常炎热，无雾，是那种让人担心变得越来越频繁的旧金山的热乎乎的夏天。大桥的五个雾角（fog horns）都没有被拉响。

While coastal fog isn’t unique to the California coast, few places in the world are so deeply associated with the ethereal movements and cooling spritz of fog’s peek-a-boo routine. Fog pours through the Golden Gate and crawls up and down the wrinkled hills of the city and the nearby coast. It cloaks and chills. Millions are affected by it, if only by the invisible cool breezes that presage the fog’s arrival.

虽然沿海雾并不是加州海岸所独有的，但世界上很少有地方与雾如此常常“躲猫猫”；加州的雾犹如空灵在游离，带着凉爽的气息。海雾穿过金门大桥倾泻而下，在城区和附近高低起伏的海岸山丘上游荡。所到之处，万物消失，凉意浓浓。数以百万计的人受雾的影响，即使只是那股预示着雾的到来的无形凉风。

Fog is why one neighborhood is notoriously chilly, another is surprisingly sunny, and the airport is where it is. It is why realtors talk about neighborhood fog patterns as much as square footage and schools. It is why fewer than half of Bay Area residents have air-conditioning, and partly why they use less water than most Americans.

雾导致一个社区非常寒冷，另一个社区却出奇地阳光明媚。当地机场所在地和雾的分布切切相关。这就是为什么房地产经纪人谈论社区的雾分布，就像谈论房地产的大小和附近的学校一样频繁。这就是为什么只有不到一半的湾区居民拥有空调，也是为什么他们使用的水比大多数美国人要少的原因之一。

Summer fog is why the mighty coastal redwoods grow where they do, surviving California’s dry season thanks to refreshing gulps of cold, wet air. It is why, until recently, few people worried about wildfires along the coast.

夏天的雾是为什么高大的沿海红杉生长在它们所在的地方。凉爽、潮湿的雾气令其能在加利福尼亚的旱季中幸存下来。这就是为什么以前很少有人担心加州沿海地区发生野火。

In June, July and August, as most of the Northern Hemisphere, and most of California, feels the full force of summer heat, the average daily high in San Francisco is below 70 degrees Fahrenheit, or about 21 Celsius, coolest of any major city in the continental United States.

在 6 到8 月，北半球的大部分地区和加州的大部分地区都感受到夏季炎热的威力，而旧金山的平均每日最高温度低于 70 华氏度，或约 21 摄氏度，是所有美国大陆主要城市中最凉爽的。

Fog is a companion, part of the rhythm of summertime, flitting in and out of lives like a family member. But it does more than astonish ill-prepared tourists and dazzle photographers and poets. It nourishes the natural world. It enriches the area’s cultural identity. It might even be an untapped resource in California’s growing anxiety over water.

雾的陪伴，是夏日节奏的一部分，像家人一样在生活中进进出出。雾的影响，不仅仅是让准备不足的游客感到惊讶（哆嗦），或让摄影师和诗人眼花缭乱。雾滋养了整个自然界。它丰富了该地区的文化特征。它甚至可能成为对用水日益焦虑的加州的未开发资源。

Which is why a decrease in California’s coastal fog, or the prospect of it disappearing entirely one day, is not a sunny proposition, particularly in and around San Francisco Bay.

这就是为什么加州海雾的减少，或者说它有朝一日完全消失的前景，并不是一个乐观的前景，尤其是在旧金山湾及其周边地区。

（待续）