The large amount of precipitation California received this winter – enough to end the five year drought in many areas of the state – has been widely reported in the news media. Northern California even had its wettest year on record. Additionally, snow pack – tracked since 1941 at the 6,800 altitude Phillips Station near Lake Tahoe in the Sierra Nevada – has been well above average consistently since February through the date of this article. There has been a steady stream of reports that ski areas are having a banner year. The reports have come both from news media and from the ski areas themselves – the latter having a financial incentive to so report and the former undoubtedly influenced by such reports. Nevertheless, skiers can attest to a respite from the snow drought. Even Southern California ski areas, which have been skipped-over by the late season storms have experienced a vastly improved ski season. In the context of climate change, these indicators seem to provide grounds for optimism.
California snow pack, even more than rain, is critical to water supply. The Spring-to-Summer snow melt provides a steady and even flow of water into the state’s reservoirs, compared to the all-at-once flows from rain storms, and extends into the state’s drier months. The steady and extended water supply from snow pack is equally if not more important for flora and fauna. As evidenced California natural treasures like Yosemite National Park, where somewhere close to half of the trees in its forests are dead, climate change and drought have left large swaths of dead brown trees among green forest. The state has lost over 100 million trees.
In the recent “good news” about the banner precipitation and snow fall, what has not been much reported is that temperatures have continued to rise. Along with this fact, storms and their precipitation have been warmer. This has meant rain where snow normally falls. As Southern Californian skiers can attest, winter storms normally snow from 3,000 – 4,000 feet in altitude on up. This past winter the snow level was typically 7,000 to 8,000 on up. As a result, snow pack started at a higher elevation than it has in the past, resulting in a smaller snow pack area. At the elevations where snow has fallen enough to accumulate, it is melting sooner. And if this summer-to-fall season follows recent trends (and science) – as it most likely will – it will be hotter, hot sooner, and hot longer. All of these conditions take a sizeable chunk out of the “good news” about precipitation and snow pack.