2026年4月18日 / 美国东部时间上午11:08 / 哥伦比亚广播公司/美联社
气象数据显示，美国本土48州的干旱程度已达到同期最高纪录。气象学家表示，这对于即将到来的野火季、粮食价格以及西部水资源问题来说都是一个不祥之兆。
根据美国干旱监测报告，超过61%的本土48州正处于中度至极端干旱状态——其中东南部地区占比97%，西部各州占比三分之二。这是自2000年该监测项目启动以来，同期干旱水平的最高值。
美国国家海洋和大气管理局的综合帕尔默干旱严重指数不仅创下了1895年有记录以来3月份的最高值，而且上个月也是有记录以来无论按哪个月份统计都排名第三的最干旱月份。仅略低于1934年7月和8月那个著名的尘 Bowl（沙尘暴）时期。
干旱提前至峰值
由于遭遇破纪录高温，西部大部分地区今年头几个月的积雪量异常稀少，而积雪通常是该地区夏季储水的主要来源。该地区经历了历史性的积雪干旱，专家警告称这可能在未来几个月引发水资源短缺和野火。联邦记录显示，新墨西哥州、亚利桑那州、科罗拉多州和犹他州的积雪量已达到历史最低水平。积雪是山区积雪的累积，融化后可为河流、水库和饮用水系统提供补给。积雪不足会使原本容易发生野火的土地变得更加脆弱。
美国国家干旱缓解中心的气候学家布莱恩·富奇表示，另一场与急流将风暴推至更北地区有关的干旱，正影响着从得克萨斯州一直延伸到东海岸的南部地区，这场干旱恰好与西部的干旱情况同时出现。
美国国家海洋和大气管理局测算，要缓解得克萨斯州东部的干旱，需要在一个月内降下19英寸的降雨；而要解决东南部大部分地区的缺水问题，则需要超过1英尺的降雨量。
“目前全国61%的地区都处于干旱状态，而且今年以来这一比例一直在稳步上升，”富奇说，“我们很少见到春季有如此大面积的国家陷入这种干旱状况。”
一个非常专业却至关重要的指标格外引人注目：大气的“海绵性”——也就是炎热干燥的空气从其烘烤的土地中吸收的水分量。这个指标被称为水汽压差。加州大学洛杉矶分校的水文气候学家帕克·威廉姆斯表示，该指标较正常水平高出77%，比西部1月至3月的此前纪录高出25%以上。
威廉姆斯说，这种从地面吸收水分的程度“在过去是不可能出现的”。
干旱通常在夏季达到峰值，而非春季，这正是气象学家担忧的原因。
“野火的发生往往与高温和干旱呈指数级相关，”威廉姆斯说，“每升高1摄氏度，野火的规模都会比上一次升温时更大。”
对水资源短缺和野火的担忧
亚利桑那大学气候适应科学与解决方案中心主任凯西·雅各布斯表示，在亚利桑那州，仙人掌提前数月开花，人们对水资源的担忧已经开始显现。
“我们这些依赖科罗拉多河的人，当然非常担心在这场似乎是我们经历过的最严重干旱之年，却没有达成协商一致的解决方案，”雅各布斯说，“我们有很多水库都没有蓄满水。”
供水预报显示，缺水情况可能即将来临，且可能大范围扩散。水资源和积雪通常可以抵御野火，作为干旱条件下的缓冲。然而，随着气温升高和积雪量持续偏低，专家表示，目前的状况越来越类似于近年来引发该地区一些最具破坏性野火的环境。
国家跨机构火灾中心警告称，由于积雪不足，西南部部分地区今年晚些时候发生重大火灾的可能性将高于正常水平。
耶鲁气候联系栏目的气象学家杰夫·马斯特斯表示，他最担心的是干旱对农业以及随后粮食价格造成的影响。如果美国因干旱遭遇歉收年景，可能会引发全球性问题。据预测，将出现强烈的自然厄尔尼诺气候振荡，这通常会降低全球其他地区（如印度）的作物产量。
加州大学洛杉矶分校的威廉姆斯表示，干旱和高温是自然变率和人为造成的气候变化共同作用的结果，其中随机性因素的影响略大一些。
“如今所有天气都会受到气候变化的影响，”亚利桑那州的雅各布斯说，“不存在脱离气候趋势的天气。但这次极端事件的极端程度符合我们的预期：极端热浪、严重干旱。”
本文另有撰稿人报道。
https://www.cbsnews.com/video/snow-drought-reaches-record-levels-in-the-western-u-s/
Record U.S. drought sparks fears about wildfires, water supply and food prices
April 18, 2026 / 11:08 AM EDT / CBS/AP
Drought in the contiguous United States has reached record levels for this time of year, weather data shows. Meteorologists said it’s a bad sign for the upcoming wildfire season, food prices and western water issues.
More than 61% of the Lower 48 states is in moderate to exceptional drought – including 97% of the Southeast and two-thirds of the West, according to the U.S. Drought Monitor. It’s the highest levels for this time of year since the drought monitor began in 2000.
The National Oceanic and Atmospheric Administration’s comprehensive Palmer Drought Severity Index not only hit its highest level for March since records started in 1895, but last month was the third-driest month recorded regardless of time of year. It trailed only the famed Dust Bowl months of July and August 1934.
Drought peaks earlier than normal
Because of record heat, much of the West has had exceptionally low levels of snow in the first few months of the year, which is usually how the region stores water for the summer. The region endured a historic snow drought that experts warn could bring water shortages and wildfires in the months ahead. New Mexico, Arizona, Colorado and Utah are contending with record-low snowpack, federal records show. Snowpack is the accumulation of mountain snow that fortifies rivers, reservoirs and drinking water systems once it melts. Low snowpack can make wildfire-prone land even more vulnerable.
A different drought — connected to the jet stream keeping storms further north — has put the South from Texas all the way to the East Coast into a separate drought that just happens to coincide with what’s going on in the West, said Brian Fuchs, a climatologist with the National Drought Mitigation Center.
It would take 19 inches of rain in one month to break the drought in eastern Texas and more than a foot of rain to solve the deficit for most of the Southeast, NOAA calculated.
“Right now 61% of the country is in drought and that’s steadily been going up for the calendar year,” Fuchs said. “We just haven’t seen too many springs where this amount of the country has been in this kind of shape.”
Sticking out like a sore thumb is a highly technical but crucial measurement of “the sponginess” of the atmosphere — or how much moisture the hot, dry air is sucking up from the land it’s baking. It’s called vapor pressure deficit. It’s 77% above normal and more than 25% higher than the previous record for January through March in the West, said UCLA hydroclimatologist Park Williams.
That level of moisture-sucking from the ground “wouldn’t have appeared possible” before now, Williams said.
Drought usually peaks in summer, not spring, and that’s what worries meteorologists.
“Fire tends to respond to heat and drought in an exponential manner,” Williams said. “For each degree of warming, you get a bigger bang in terms of fire than you got from the previous degree of warming.”
Worries about water shortages, wildfires
In Arizona, cacti are blooming months early and the worry about water has already started, said Kathy Jacobs, director of the Center for Climate Adaptation Science and Solutions at the University of Arizona.
“Those of us who are dependent on the Colorado River, of course, are very concerned about the fact that we don’t have a negotiated path forward in the middle of what appears to be possibly the worst year of drought that we’ve all experienced,” Jacobs said. “We have lots of reservoirs that are not full.”
Water supply forecasts suggest shortages could be imminent and potentially widespread. Water and snowpack usually protect against wildfires, acting as a buffer against dry conditions. However, as temperatures rise and snowpack remains low, experts said conditions taking shape increasingly resemble those that in recent years have fueled some of the region’s most destructive blazes.
The National Interagency Fire Center warned that the potential for significant fires would be higher than normal for parts of the Southwest later in the spring, in part due to snowpack.
Yale Climate Connections meteorologist Jeff Masters said his biggest concern is what the drought will do to agriculture and then food prices. If America has a poor crop year due to the drought, it could be a global problem. A strong natural El Niño weather oscillation is predicted, which often reduces crop yields in other parts of the globe, such as India.
UCLA’s Williams said the drought and hotter weather are driven by both natural variability and human-caused climate change with randomness a slightly bigger factor.
“All weather is now affected by climate change,” Arizona’s Jacobs said. “There is no such thing as weather that’s divorced from climate trends. But this extreme event is extreme in the way that we’ve been expecting: extreme heat waves, intense drought.”
contributed to this report.
https://www.cbsnews.com/video/snow-drought-reaches-record-levels-in-the-western-u-s/
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