【中美创新时报2024 年 11 月 29 日编译讯】（记者温友平编译）随着地球继续升温，有意阻挡太阳辐射的想法——有时被称为太阳辐射改造、太阳地球工程或气候干预——正在引起人们的关注。政府、大学、投资者，甚至环保主义者都在投入数百万美元用于地球工程系统的研究和建模。《纽约时报》记者克里斯托弗·弗拉维尔对此作了下述详细报道。
在落基山脉脚下的一个戒备森严的院落里，政府科学家正在研究一种新型的全球警报系统：它可以检测到另一个国家，或者可能只是一个冒险的亿万富翁，是否试图遮蔽太阳。
每隔几周，博尔德的研究人员就会放飞一个气球，气球会升到 17 英里高的天空。类似的气球以较低的频率从阿拉斯加、夏威夷和新西兰、非洲海岸附近的留尼汪岛甚至南极洲发射。它们构成了一个系统的基石，该系统会向美国科学家发出地球工程警报。
随着地球继续升温，有意阻挡太阳辐射的想法——有时被称为太阳辐射改造、太阳地球工程或气候干预——正在引起人们的关注。政府、大学、投资者，甚至环保主义者都在投入数百万美元用于地球工程系统的研究和建模。
这可能是一种相对快速的地球降温方法。但也可能引发难以言喻的危险。
许多人担心，太阳地球工程可能会带来意想不到的后果，破坏区域气候模式，破坏从农业到地方经济的一切。而且第一步可能会由一个不法之徒或另一个国家悄悄地完成，不受任何监管或控制。
因此，美国正在建立一个系统，使其能够确定其他国家是否以及何时可能试图篡改地球的恒温器。
“这是当今世界上最重要的平流层科学研究之一，”美国国家海洋和大气管理局化学科学实验室主任戴维·W·法希 (David W. Fahey) 最近一天下午在博尔德的办公室里说，该实验室正在建设气球哨兵网络。
NOAA 和 NASA 都有可以探测大气中大量气溶胶的卫星，但它们无法探测到较少量的气溶胶。这就是气球的作用所在。每个气球都携带一个 6 磅重的装置，大小与午餐盒相当，里面装满了电线和管子。该装置可测量微小的空气传播颗粒或气溶胶。气球的跃升可能表明平流层中存在异常数量的气溶胶，可能将部分太阳热量反射回太空。
Fahey 的团队正在建立检测、跟踪和了解任何异常气溶胶释放影响的能力。
地球工程的早期预警系统是一项分散在联邦机构和实验室的努力。NOAA 拥有测量气溶胶浓度并在任何异常情况发生时发出警告的设备。NASA 拥有高空飞机，可以携带精密的测试设备到达气溶胶羽流的位置。美国能源部新墨西哥州桑迪亚国家实验室的科学家拥有一种工具，可以估算气溶胶爆发的时间和地点。
研究人员强调，这些探测工作仍处于起步阶段。截至目前，他们认为，尽管阴谋论者声称太阳能地球工程已成功，但其规模还很小。
但美国国家海洋和大气管理局和桑迪亚国家实验室开展的工作表明，地球工程已从科幻小说中的内容转变为政府日益关注的问题。
“如果一个国家——主要盟友或主要对手——正在建设能力，我们的科学家能否告诉我们他们正在尝试做什么以及会产生什么影响？”SilverLining 的创始人兼执行董事 Kelly Wanser 问道。SilverLining 是一个倡导地球工程研究并帮助说服国会资助 NOAA 项目的非营利组织。“这有多危险？我们需要多快、多努力地做出反应？”
NOAA 在博尔德运营的化学科学实验室给人一种大学校园的感觉。一些世界顶级大气科学家穿着登山靴和 T 恤在展厅里漫步，仿佛准备攀登透过窗户可见的落基山脉。唯一能表明他们工作性质的迹象是门口的武装警卫，他们正在搜查来访车辆是否装有爆炸物。
在一个没有窗户的房间里，专注于研究气溶胶微观物理特性的年轻法国科学家亚历山大·巴伦 (Alexandre Baron) 展示了他的团队一直送上天空的盒子的内部结构。该设备将空气吸入进气管，并用激光扫描。气溶胶散射光线，从而可以记录它们的浓度和大小。
一旦携带设备的气球上升到 90,000 英尺的高度（几乎是客机巡航高度的三倍），阀门就会打开，慢慢释放氦气，使气球飘回地球。往返需要 3 个半小时，在此期间，仪器会通过无线电将气溶胶读数发回地面。
NOAA 找回了大部分箱子，每个箱子大约 15,000 美元，更换了零件，以便再次使用。（该机构在海上和阿拉斯加荒野中丢失了一些气球。）
有时，气球和它珍贵的货物会缠在树上。在 Baron 的房间，在实验室设备中，靠墙放着一把大型树木修剪机。负责该项目的 NOAA 研究科学家 Troy Thornberry 说：“有一次，我肯定用过它，当时载荷被吊起来了。”
博尔德科学家的当务之急是收集足够多的有关地球上空不同地点气溶胶水平的数据，以建立正常浓度的基线，除非发生火山爆发等外部事件。这将使 NOAA 能够确定任何特定地点的气溶胶水平何时异常高。
索恩伯里说，该计划于 2020 年开始由国会资助，符合 NOAA 研究大气的更广泛使命。他补充说，预算每年不到 100 万美元。
为了建立全球基线，NOAA 一直在与其他国家的研究人员和政府科学家合作。它正在与毛里求斯附近的法国领土留尼汪岛的研究人员协调发射。本月，NOAA 工作人员首次从巴西北部边境的一个小国苏里南发射了一只气球，并计划未来由该国的气象机构负责发射。
索恩伯里说，美国希望在全球七个地点建立定期气球发射点，并将这些发射维持三到五年。他说，到那时，该机构应该有足够的信息来自信地识别异常增长。
索恩伯里说，他不知道还有其他国家在进行类似的监测工作。“也许是因为他们只是不谈论它，”他补充道。
本文最初发表于《纽约时报》。
题图：左图为负责新西兰气球发射工作的大气科学家理查德·奎雷尔 (Richard Querel)，右图为大气技术员佩妮·斯梅尔 (Penny Smale)，他们正在为从新西兰劳德发射气球做准备。图片来源：Tatsiana Chypsanava 为《纽约时报》拍摄
附原英文报道：
The US is building an early warning system to detect geoengineering
By Christopher Flavelle New York Times,Updated November 28, 2024
Richard Querel, an atmospheric scientist who runs the balloon launches out of New Zealand, left, with atmospheric technician Penny Smale in preparation for a launch from Lauder, New Zealand.Credit…Tatsiana Chypsanava for The New York Times
BOULDER, Colo. — In a guarded compound at the foot of the Rockies, government scientists are working on a new kind of global alarm system: one that can detect if another country, or maybe just an adventurous billionaire, tries to dim the sun.
Every few weeks, researchers in Boulder release a balloon that rises 17 miles into the sky. Similar balloons are launched with less frequency from sites in Alaska, Hawaii, and New Zealand; Reunion Island, near the coast of Africa; and even Antarctica. They make up the building blocks of a system that would alert US scientists to geoengineering.
As the planet continues to heat up, the idea of intentionally trying to block solar radiation — sometimes called solar radiation modification, solar geoengineering, or climate intervention — is gaining attention. Governments, universities, investors, and even environmentalists are pouring millions of dollars into research and modeling of geoengineering systems.
It could be a relatively quick way to cool the planet. But it could also unleash untold dangers.
Many worry that solar geoengineering could have unintended consequences, shattering regional weather patterns and damaging everything from agriculture to local economies. And the first steps could be done quietly, by a rogue actor or another nation operating without any regulations or controls.
So the United States is building a system that would allow it to determine if and when others may be trying to tamper with Earth’s thermostat.
“It’s some of the most important stratospheric science going on in the world today,” David W. Fahey, director of the National Oceanic and Atmospheric Administration’s Chemical Sciences Laboratory, which is building the network of balloon sentries, said on a recent afternoon in his office in Boulder.
Both NOAA and NASA have satellites that can detect large quantities of aerosols in the atmosphere, but they can’t pick up smaller amounts. That’s where the balloons come in. Each one carries a 6-pound contraption, about the size of a lunchbox, filled with wires and tubes. The device measures tiny airborne particles, or aerosols. A jump could indicate the presence of an unusual amount of aerosols in the stratosphere, possibly to deflect some of the sun’s heat back into space.
Fahey’s team is building the capacity to detect, track, and understand the effects of any unusual aerosol release.
The early warning system for geoengineering is an effort splintered across federal agencies and laboratories. NOAA has the device to measure aerosol concentration and raise a red flag at any anomalies. NASA has the high-altitude aircraft that can carry sophisticated testing equipment to the location of an aerosol plume. Scientists at Sandia National Laboratories in New Mexico, working for the Energy Department, have a tool that can estimate when and where a burst of aerosol was emitted.
Researchers stress that these detection efforts are still in their infancy. As of now, they believe that solar geoengineering has only been attempted at a very small scale, despite the claims of conspiracy theorists.
But the work taking place at NOAA and Sandia demonstrates how geoengineering has transformed from the stuff of science fiction to a source of growing concern for the government.
“If a country — a major ally or a major opponent — is building up capabilities, can our scientists tell us what they’re trying to do and what the impact of that would be?” asked Kelly Wanser, founder and executive director of SilverLining, a nonprofit group that advocates for geoengineering research and helped persuade Congress to fund NOAA’s program. “How dangerous is that? How fast and hard do we need to respond?”
The chemical sciences laboratory that NOAA operates in Boulder has the feel of a college campus. Some of the world’s top atmospheric scientists roam the halls in hiking boots and T-shirts, as if ready to hike up the Rocky Mountains that are visible through the windows. The only hint of the nature of their work is the armed guards at the gates, sweeping visiting vehicles for explosives.
In a windowless room, Alexandre Baron, a young French scientist who focuses on the microphysical properties of aerosols, displayed the innards of the boxes his team has been sending aloft. The device pulls air into an intake tube and scans it with a laser. The aerosols scatter the light, making it possible to record their concentration and size.
Once the balloons carrying the devices ascend to 90,000 feet, almost three times the cruising altitude of a passenger jet, a valve opens to slowly release helium and cause the balloons to drift back to Earth. The round trip takes 3½ hours, during which time the instruments send aerosol readings back to the ground by radio.
NOAA retrieves most of the boxes, which cost about $15,000 a piece, replacing components so they can be used again. (The agency has lost some of the balloons over the ocean and in the Alaskan wilderness.)
Sometimes a balloon and its precious cargo get tangled in trees. Leaning against the wall in Baron’s room, among laboratory equipment, was a large tree pruner. “I definitely used it on one occasion where the payload was strung up,” said Troy Thornberry, the NOAA research scientist in charge of the program.
The immediate task of the scientists in Boulder is to gather enough data about aerosol levels at different spots above Earth to create a baseline of normal concentrations, absent some outside event like a volcanic eruption. That would allow NOAA to determine when aerosol levels at any particular spot are unusually high.
The program, which Congress began funding in 2020, fits within NOAA’s broader mission to study the atmosphere, Thornberry said. The budget is less than $1 million a year, he added.
To build a global baseline, NOAA has been working with researchers and government scientists in other countries. It is coordinating launches with researchers in Réunion, a French territory near Mauritius. This month, NOAA staff launched a balloon for the first time from Suriname, a small country on Brazil’s northern border, with plans for future launches run by that country’s meteorological agency.
The United States wants to establish regular balloon launches from seven sites around the world and maintain those launches for three to five years, Thornberry said. At that point, the agency should have enough information to confidently identify unusual increases, he said.
Thornberry said he’s not aware of any other countries pursuing a similar surveillance effort. “Maybe because they just don’t talk about it,” he added.
This article originally appeared in The New York Times.
