Climate change is threatening giant Sequoias and threatening ecological disaster. Sequoias, once deemed “unburnable,” began to be widely destroyed by fire in 2015, and then in 2020 and 2021, California fires tripledArea covered. The currentBest count of mature Sequoias killedIncreased fire intensity since 2015 is greater than 13,000. There are only about 75,500 mature sequoias in existence. The National Park Service defines mature trees as those that are greater than 4 feet in size.
There are approximately 73 giant sequoia grovesIn existence, and more than 85 per cent burned between 2015-2021. Only 25 percent of the groves were left in the 100 years preceding. burned.
“Large sequoias typically died by falling or, occasionally, having extensive crown scorch from fire,” where “crown scorch” is fire that kills but does not consume tree needles. The National Park Service continues, “Death while standing, unrelated to crown scorch, was almost never observed by scientists who had spent decades working in the Sierra Nevada. And while mature giant sequoias did die from fire impact, that was a relatively rare event, typically the result of many accumulated injuries over their long lives.”
Some of these sequoias may have been as old as 3,000 years. These sequoias have lived to nearly impossible ages, battling fire over and over again, and have even become fire-proof. Their soft, asbestos-like bark can grow up to two to three inches thick. They don’t have flammable resin like almost all other conifers, and their great height, where their lowest branches can be 150 to 200 feet above the ground, allows them to tower over the other forest trees that when in flame are far below the needles of sequoias.
“The hotter drought of 2012-2016 appears to have been a tipping point for giant sequoias and other Sierra Nevada mixed-conifer forests,” the National Park Service reports. “In hotter droughts, unusually high temperatures worsen the effects of low precipitation, resulting in greater water loss from trees and lower water availability. This is an emerging climate change threat to forests.”
Global warming has caused an increase in evaporation across the West and Southwest. This has led to massive tree deaths from drying and drying-induced attack by native bark beetles. California is the worst affected state. 172 million treesSince 2010, more than 100 to 200 millions people have been killed by beetles, drought, and disease. The fires that erupted in 2021 killed between 100 and 200 million. During Texas’s record drought between 2011 and 2013, more than 300 million trees were killed, and the state’s ongoing drought is now more severe than the last. All over the North American West 100 million acresSince 2017, trees have been greatly impacted or almost completely killed by native bark mites.
New Mexico saw its two largest wildfires in a single year in 2022. In 2020, Colorado saw its three largest wildfires in a single year. Since 2017, California has experienced eight of the most destructive wildfires. The new record fires that California has seen in 2017 were all larger than 300,000. These were the two largest fires ever reported in California. 1 million acresEach of them, in 2020 or 2021. The seven largest firesCalifornia history has burned since 2018. California has seen the largest wildfires since 2018. doubled in sizeFrom the 2000s through 2018, and then doubled again in 2020, to 1,000,000 acres each fire.
The main argument about the reason for this threshold passing is that wildfire suppression over the past 100 to 200 years has allowed forest fire fuels to grow, which, in combination with increased heat and increased drought due to climate change, has increased high-severity fire to the point of being uncontrollable. 800 percentSince 1985. About 900 people are killed by high-severity fires. 95 percentThe loss of tree species and the deterioration of soil conditions post-fire reduces regeneration and increases the risk of forests being converted to other vegetation types such as shrubs and grasslands.
A third of the fires that were lit in the American West around the turn of this century are located in the American West. not regeneratingThe former forest is too dry to support seedlings. These forests are being regenerated as shrubs and grasslands. Half of those fires that are showing some regeneration are regenerating at half their 20th century rate. We are now in an era when pre-fire forests are scarce. may not return. Forest species cannot return without forests. Cloud machines are also forests, and when they are gone, so are the clouds.
This is a serious failure in regeneration. An astonishing example of forest conversion to grassland is the result of fires in Colorado’s Mesa Verde National Park from 1998 to 2001. They destroyed more than half the forest in the park, and nearly all the forests on the mesa summits. These forest resources were used by the ancient Puebloans for subsistence. The likely reason they abandoned their cliff dwellings 700 year ago was drought. The mesa top forests have survived throughout and after that time. The Pinyon/juniper woodland, which remained after the Puebloans left, has been replaced by a grassland. It has not yet begun. regenerate after 20 years. This is all natural. But what about the wider implications?
Six climate change-caused fire enhancing behaviors, in addition to higher fuels, are also available increasingArea burned and severity of fires – Record dry fuels from climate changes drought, record low humidity, higher temperatures creating easier incense and more extreme burning, and record wind storms. Longer drying with earlier springand the later onset of fall conditions. increased nighttime fire behavior. These factors have led to the California Department of Forestry and Fire Protection’s (CAL FIRE), declaring that fires are now raging 400 degrees hotter.
For 30 years scientists have warned of climate tipping systems that could activate if we don’t take action to reduce climate pollution. Tipping systems are Earth systems such as the Amazon and permafrost. They can withstand a lot of abuse, such as drying, fires, and higher temperatures, until eventually the species or the ice in the permafrost collapses. These tipping system are the irreversible impacts of climate change that were not expected to occur until the end the century. Tipping systems that fail are unable to provide the necessary environmental services. They can be destroyed, eliminated, or reversed. Carbon dioxide sequestration is one the most important environmental services. Canadian forests are currently in collapse, largely due to the native bark beetle infestations. They now emit carbon dioxide and not absorb it. 250 million tons2020: The annual average of greenhouse gases per year Permafrost emits, not absorbs, 2.3 billion tonsEvery year, more greenhouse gasses are released into the atmosphere. 1 billion tonsEach year, greenhouse gases are released into the atmosphere.
A 2019 article in the journal NatureThe tipping activity was active in half of known tipping systemsThere was consensus that tipping would not activate until temperatures reach 5 degrees Celsius by the year 2100. These tipping systems are currently active: Arctic sea ice and Greenland ice sheets, boreal forests. permafrost. The Gulf Stream, Amazon, coral, West Antarctic Ice Sheet, and parts of the East Antarctic Ice Sheet.
Tipping (or Earth systems collapse) occurs when the evolutionary boundaries of those systems are crossed. This is simply system evolution, where conditions become hostile for the species that evolved in the system. The system then collapses with new species that are more tolerant of the altered condition.
The threshold for climate change has been reached. We have warmed beyond the evolutionary boundaries of our Earth’s systems. “Starting in 2015, higher-severity fires have killed mature giant sequoias (those 4 feet or greater in diameter) in much greater numbers than has ever been recorded,” the National Park Service reports. “We have reached a tipping point — lack of frequent fire for the past century in most groves, combined with the impacts of a warming climate — have made some wildfires much more deadly for sequoias.”
The evolutionary boundaries of our Earth’s systems are what made our advanced civilization what it is. Earth’s systems evolved within the boundaries of our old climate and our advanced human civilization evolved dependent upon our Earth’s systems. Can civilization survive without these systems. Can we adapt? Do we use metal or plastic to make our products? Where is the water that the forests provided that watered our crops and our industry? What happens to the jobs once the forests are gone
Additional warming to the established 1.5°C target ensures that these prematurely activated tipping collapses are complete and become irreversible. These Earth systems that are in tipping collapsing are much more than just the green in the surface, the fish in the oceans, and the unseen biota within our soils. They provide the environment services we need for a stable climate.
Earth’s species matter. A stable sea level matters. Sequoias — some of the oldest and most noble things on the planet — they matter. They are the harbingers. Earth’s system collapses do not self-restore unless the perturbation is removed; unless the warming is removed.
What we need to do now is become motivated to reduce our climate culture’s warming target from 1.5°C, to less than 1°C to prevent these already activated climate tipping systems from becoming existentially irreversible.
The author would love to be thanked Sue Cag, whose photographs provided a remarkable firsthand view of the huge sequoia casualties.
A longer version of this articleWith in-depth references, it is at Climate Discovery.
