The Past is Not Prologue in the American Pacific West

Accomplices of an arid climate, 长期以来，野火和干旱给美国太平洋西部带来了破坏.

“我们知道，这些系统以前经历过严重的干旱。. Benjamin Cook, 他是美国宇航局戈达德太空研究所(GISS)和哥伦比亚大学的气候科学家. “In fact, 如果我们回到一千年前的中世纪，当时美国西部正在经历我们所说的“特大干旱”,“这些干旱事件比20世纪经历的任何事情都要持续得多，而且往往范围更广.”

但有一个因素将过去几个世纪的灾难与现代极端天气区分开来:干旱和高温.

“Big droughts are not unprecedented. 前所未有的是，我们在应对这些干旱的同时，气温却要高得多,” Cook explains.

科学家表示，自1880年以来，地球上的全球平均温度一直在上升 by nearly 2 degrees Fahrenheit. Now, 气候变化加剧了美国西部炎热的空气和干燥的土地之间的危险.

“只要气候继续变暖，这些影响就会持续下去，而且可能会加剧.”

A CHANGING LANDSCAPE

Extensive research shows climate change is increasing the intensity and frequency of natural disasters. In the American Pacific West, 气候变化带来了严重的干旱，这与不屈的干旱同义. Plants and trees dry out and the vegetation piles up on the forest floor. This brush feeds wildfires making them burn hotter and spread faster.

This increased intensity is inflicting more severe, long-term damage. Whereas forests were previously able to regenerate after a wildfire, the effects of climate change are diminishing their natural ability to heal. Cook says once the land does recover, it’ll likely look different.

“一个更容易发生火灾的西部仍然会有植被、生态系统和物种, 但它会有适应在这种条件下茁壮成长的物种. 哪些物种可能与我们历史上与这些生态系统相关的物种不同,” Cook explains.

气候变化引起的生态系统构成的一些重大变化已经被观察到.

In California, 研究人员表示，现在太热了，至少20%的内华达山脉针叶加拿大28回水无法繁殖. That means once these ‘zombie forests针叶加拿大28回水一旦灭绝，就会被一种完全不同的物种所取代. Researchers 加州大学河滨分校的研究人员发现，索诺兰沙漠的植物物种也在移动. Species that have long been recognized for their resiliency, like the pinyon pine, are shifting upwards in elevation in search of cooler temperatures. And species with shallow root systems, like brittlebush, are moving into the hotter, low-elevation vacancies.

The Future Plant Hardiness Zone Map 来自植加拿大28回水节基金会和戴维加拿大28回水木专家公司的详细介绍了未来几十年太平洋西部植被茁壮成长的更多变化.

物种的变化可能比简单的物种在哪里存在有更大的影响. Right now, about 75 percent of the country’s fruits and nuts 都是加州本土种植的，还有全国30%的蔬菜. Regardless of if you live in the Pacific West or not, most of us look to the region for its agriculture. 但气候变暖可能会抑制通常在那里蓬勃发展的商品，并可能造成粮食短缺.

While many plants and animals are moving out, humanity continues to lay down sturdy roots in the American Pacific West.

PROACTIVE RATHER THAN REACTIVE

As the population in the Pacific West has grown, residential developments have pushed into ecosystems that naturally burn. Data from the U.S. Forest Service shows that in 2020, more than 16 million homes in the Pacific West were located in fire-prone areas. That’s up from about 10 million homes 30 years prior.

“即使是这些处于火灾易发生态系统中的一些城镇，也没有围绕减少火灾的最佳做法建立起来,” Cook says. “You can’t just stop fire, especially in the context of climate change. 但是有办法控制火灾，可以减少这些破坏性事件发生的可能性.”

Cook believes that begins with a sense of intentionality.

“The nature of the human condition is that we tend to be very reactive. 一些不好的事情发生了，然后我们开始想办法摆脱它，”库克说. “For the first time in human history, 我们对未来50到100年将会发生什么有一些合理的想法. That’s powerful because now we can actually plan around it.”

For example, 下水道系统通常是根据历史风暴事件的强降雨统计数据设计的.

“But if climate is changing the status quo and changing those statistics, 那就意味着你建造的下水道系统已经不足以防止洪水了,” Cook explains. “We need to build that for the climate in 50 years, not for the climate today or the climate from a hundred years ago.”

In the Pacific West, 适应气候变化的基础设施可能看起来像改变我们悬挂电线的方法, which are known to spark wildfires. 它可能包括改变水的分配，特别是在干旱时期.

“In this case, the past is not prologue. 我们不能通过回顾20世纪中期发生的事情来预测未来会发生什么,” Cook notes.

BENCHMARKS FOR SUCCESS

When looking to the future, 库克认为，在应对气候变化的斗争中，设定正确的成功基准是关键. 太平洋西部和世界各地生态系统的动态特性, there are going to be both triumphs and failures.

“The Paris Agreement 设定这个“2摄氏度”的目标，但如果我们超过2摄氏度，并不意味着游戏结束. 如果我们保持在2摄氏度以下，并不意味着我们不必担心任何事情，”库克说.

The best thing we can do for the planet is keep moving forward. Keep trying. We’ll never be able to return the Earth to the pristine nature of its origin. But we can nurture it. We can plant trees in the right places to help improve climate, communities, and biodiversity. We can protect habitats for wildlife. 我们可以重新思考旧观念，制定更好、更具气候适应性的解决方案.

We just need to get started.

“我认为值得实现的是管理这些生态系统，以平衡物种和人类的使用. Obviously, there’s a lot of actors and there’s lots of interests, but I think we can do that,” Cook says. “我们只需要在做这件事的时候，考虑到在气温升高2到3度的世界里会是什么样子.”