Fire, Part 5: Wildfire Revelations
Saturday, February 20th, 2021: Fire, Nature, Wildfire.
All images by Max unless otherwise credited.
Previous: Recovering in Burn Scars
Wildfire and Habitat
Throughout these Dispatches on wildfire, I’ve been using the word habitat as if we’re all familiar with it and understand it in the same way. But is that true?
In ecology – the study of relationships between living organisms and their environment – habitat means, to quote Wikipedia: “the array of resources, physical and biotic factors, present in an area that allow the survival and reproduction of a particular species.” Your habitat is the area around your home where everything you need comes from: air, water, food, shelter, healthcare, etc.
But because many organisms range widely for the resources they need, habitat can be hard to pin down. We’re most familiar with birds – they can seemingly go anywhere. For some migrating birds, their habitat would seem to be an entire hemisphere of the earth. Whales, of course, also migrate thousands of miles. But even a colony of ants can live in a forest and harvest food from a nearby meadow – and vice versa.
As Wittgenstein observed, language is a game. The meanings of words are not prescribed in advance by dictionaries; words acquire meaning during use, and dictionaries are compiled after the fact to report on the usage of words in society.
Experiencing firsthand the changes wrought by wildfire in the Southwestern landscape, I’ve groped for words to describe and share my experience. When biologists, conservationists, and land managers get together in the field, I’ve always heard them refer to a forest, a grassy meadow, a desert, a stream corridor, or a seashore as a type of habitat – for example, “You’ve got that forest habitat next to a sagebrush steppe.” In that usage, habitat doesn’t refer to a single species and its needs, it refers to a physical area hosting and providing the needs of a distinct community of countless different species – from bacteria and fungi to trees and large mammals – whose interactions with each other and the nonliving components of that area constitute an ecosystem. That area, that type of habitat, has boundaries, beyond which it ends and other, adjacent types of habitat begin, and it’s defined in terms of the recognizable features that distinguish it from other, adjacent habitats. For example, a forest bordering on a meadow, or an ocean bordering on a coast.
Biologists are not really supposed to use the term “habitat” in that vernacular sense, as a place defined by a geographical feature, or an alliance of dominant vegetation, hosting a distinct community of species. But we need a word for such a place, and we grope for something more accurate.
Wildfire makes this need even more urgent. Within hours, a wildfire can turn a forest full of trees and the animals that depend on them into a smoking, ash-blanketed moonscape. The forest provided habitat for countless species, but what do you call the empty moonscape? And when, after monsoon rains, the ashy wasteland is gradually replaced by clumps of annual wildflowers here, stands of ferns there, isolated thickets of aspen here, scattered oak seedlings there, with birds and other animals moving back and forth between them – what do you call the new landscape? The theory of succession says that the new regime is transitory. Over time, species will grow and spread, competing for light, space, water, and nutrients. The perennials all start small, but some will end up dominating others.
That takes time – decades and human generations, in the case of this former forest – and in the meantime, what used to be distinct, homogenous habitat is an unstable, transitional mosaic of patches. Countless plants and animals begin using it immediately after the fire and increase in numbers and complexity from then on. The “new normal” is evolving, but it still provides habitat for these species.
Thus wildfire forces us to talk about habitat that’s divided into a mosaic of patches that are ever-changing and shared between countless species that overlap in some sort of dynamic network. Just as we defined the previous, larger, homogenous and stable area by its most recognizable features, we define each evolving patch by the features that are temporarily dominant. The more we strive for precision and follow the mandate of reductive science to focus on individual species, the more wildfire forces us to take a holistic view.
Desert Fires, Forest Fires
Across my four decades in the Mojave Desert, I can think of only three memorable wildfires. The small one I woke up to in 1989, described in Part 2, is the only one I know firsthand. The other two, the Hackberry Fire of 2005 and the slightly smaller Dome Fire that decimated our most famous Joshua Tree forest in 2020, consumed less than 200,000 acres. During that same period, the forested mountains of Arizona and New Mexico have experienced dozens of mega-wildfires consuming millions of acres. Whereas the prehistory of wildfire in the desert is poorly known and controversial, the forests of the Southwest are widely acknowledged to be adapted to and dependent on wildfire.
During my lifetime, the frequency and intensity of wildfire have increased in both habitats. Most “environmentally-conscious” people now assume that climate change is at fault, simply because media authorities have oversimplified climate change into the scapegoat behind all our environmental problems. But fire suppression, not climate change, is the main reason why more forests burn now than in my youth. Wildfires would’ve been common decades ago if our government hadn’t prevented and aggressively fought them.
Anyone can recognize that a warmer, drier climate will dry out both living and dead vegetation, increasing the risk of fire. But the desert and the forest pose very different risks.
Yes, reductive science tells us that the loss of forest reduces absorption of carbon by the “biosphere,” accelerating climate change on a planetary scale. But Southwestern forests are meant to burn, and the resulting habitat mosaic can be more diverse and productive than the artificial uniformity we created through fire suppression. The forest needs wildfire to restore its balance.
Not so in the desert. As I described in Part 3, unlike the Southwestern forests, desert habitats are being degraded and lost at an ever-accelerating rate due to invasive plants – and of course, due to urban and industrial development – particularly the misnamed “green” energy. Wildfire in the already extremely arid desert will explode in future decades as our rapidly increasing demand for electricity – misbelieved to be a “clean” source of energy – sparks more infrastructure fires, and as more and more invasive plants spread by our “green” electric vehicles provide more and more fuel for high-intensity wildfire, clearing more and more native habitat and replacing it with degraded, biologically impoverished land dominated by aliens.
We Europeans were wrong to call it a desert when we first saw it, because back then, it was a diverse, productive wonderland. Now, we’re making the place fit the name – a wasteland created by our expansion and innovation, a victim of civilization and progress.
Forest Reborn in Fire
Science doesn’t really answer all our questions or provide a definitive explanation for what happens in nature – science provides simplified abstractions that can mislead us into thinking nature is orderly and can be controlled by us.
In the ideal, theoretical, stable habitat, with a stable climate, stable landforms, and a stable ecosystem or community of organisms, scientists tell us that wildfire occurs in a pattern they call the fire regime. Within that theoretical regime, wildfire occurs in fire cycles, meaning that fires repeat at more or less regular time intervals. Each fire is followed by a more or less predictable sequence: flooding, erosion, deposition, plant invasions and colonizations, a period of decomposition, competition, and instability, eventually leading to a stable state in which the habitat and community are just waiting for the next fire.
In this theoretical model, climate – the yearly cycle of weather, from wind and cloud cover to precipitation, temperature averages and extremes – enables specific communities of organisms to settle into specific niches where, working together, they establish distinct habitats and ecosystems, adapting to wildfire and further shaping its regime – its pattern – and its cycle. This is ecology in the broadest sense – living and nonliving, earth and sky, ephemeral phenomena and stable pattern – working together to achieve what in my field of science – the science of motion and change – was called a dynamic equilibrium.
A particular fire regime, and its corresponding cycle, are of course determined by habitat, which is in turn determined by landscape, its geological foundations, climate, and evolutionary history. Regardless of climate, mountains create elevational zones of habitat, from the desert basins to the arid grasslands, the mid-elevation, fairly open forest of trees with spreading crowns, and the high-elevation mixed-conifer forest of tall, slender trees creating a more or less solid canopy. Mountains create corridors and niches of habitat via their rock substrate, their peaks, ridges, rock outcrops and cliffs, and canyon bottoms. Patches of fast-burning fuel – accumulations of dry or dead vegetation, especially from invasive plants – provide a ready-made path for wildfire, diverting it away from slower-burning patches. Both habitat and landforms create the potential for fire and shape its spread.
Within a distinct habitat and ecosystem, the fire adaptations of species, and the conditions of individuals – their relative age and health – determine how they react to fire, and how fire may cull weak or unhealthy individuals while protecting the population. The thick bark on the trunks of mature pines and firs acts as insulation, protecting the sapwood inside. Mature trees shade and kill their lower limbs, which fall off, denying surface fires a “ladder” of fuel to climb to the crown. This is particularly effective for ponderosa pines, which have thick branches that could offer substantial fuel.
Succulents like agave, yucca, and cactus, which we think of as natives of the open desert, thrive in the fire regime of forests because their stored water and underground mass cools and protects them from total destruction in a wildfire, so that even if their thick leaves are completely killed, the plant’s hidden heart can still bear fruit.
In southwestern New Mexico, we may reference the four seasons of our European cultural legacy for convenience, but those are not the seasons we get. Our windy season, in March and April, dries out the land, increasing fuel for wildfire. May and June, the buildup to the Southwest monsoon, bring heat and dry lightning in the mountains. Most of our wildfires start in May and June.
If we get a good monsoon, starting in July, rains will start to suppress the fires. Climate is the pattern, weather is the expression, preparing the land for burning, lighting the fires, then putting them out.
We all know how wildfire can be started by lightning strikes. But did you know that rocks falling against each other can spark wildfire?
Humans start wildfires through carelessness – like the campers in Arizona’s White Mountains who left their campfire smoldering and started the largest wildfire in the history of the Southwest. Or by malicious intent, like the arsonist(s) who destroyed the forest on the little peak I hiked near town.
Our advanced technologies are simply too complex for us to control and keep safe. A driver pulls onto the weedy shoulder of the road to take a call, her hot exhaust pipe catches the weeds on fire, then she drives away, oblivious. Small engines are used millions of times every day at the urban-wildland interface – chain saws, weed-whackers, lawnmowers – generating sparks that can cause wildfires.
Recently, some of the most destructive fires at the urban-wildland interface have been started by arcs or failures in electric power distribution systems. As we try to slow climate change by transitioning from fossil fuels to electric cars, the increased demand on electrical infrastructure will spark more wildfires.
Indigenous people have always started wildfires to increase the productivity of habitat, and Europeans have belatedly appropriated indigenous practices in North America. Fires with a non-human cause burn according to non-human constraints of landscape, habitat, and weather. Humans may schedule, locate, and direct their fires – a prescribed or controlled burn – for defined purposes like “fuel reduction.”
Once a fire has started, it develops a life and history of its own. It’s intuitive for us to think of fire as a thing – even a living thing – but in the reductive domain of European science, fire isn’t a distinct thing, it’s an ephemeral state or property of the “matter” which is burning at the moment. The flames consuming a tree, and the flames consuming its neighbor, are not considered a continuous entity or phenomenon. From the perspective of physics and chemistry, it’s all just atoms, molecules, and energy.
But in the real world, fire is most definitely a living thing. A wildfire is born, it grows, it travels. It may merge with a neighboring fire, like two cells fusing. Like living organisms, it’s always dying even as it grows and thrives – embers blackening and cooling in one place while flames blossom in another. Fires that spread from a center die from the inside out, an expanding ring of flames surrounding a blackened core.
But the movements of fire are directed by landscape, weather, and habitat. In mountains, in still air, a fire will burn uphill. But air is seldom still in mountains, and fires generate their own winds. Strong winds may carry sparks for miles to give birth to spot fires, children isolated from the parent. While moving, a fire may encounter fast-burning fuel that draws it forward. Or it may hit an obstacle – a patch of wet or slow-burning vegetation, a cliff or rock outcrop, the sharp crest of a ridge, a river, pond, or lake. The obstacle may stop the fire, force it to detour, slow it down, or simply reduce its intensity. Obstacles or patches of low intensity provide refuges for plants and fleeing animals.
Depending on cause and habitat, a fire may spread through soil – a ground fire – through surface vegetation – a surface fire – or from treetop to treetop – a crown fire. But these are just convenient abstractions – the reality is much more subtle and complex.
A fire is said to make a run – burning a path uphill, downhill, or across country – directed by landforms, temperature gradients, wind currents, and the availability of fuel. In a complex landscape, it moves like an amoeba, an amorphous being, drawn to patches of available fuel.
Burning vegetation generates smoke, clouds of particulates and gases that warn animals, trigger reactions in plants, release nutrients, and rise into the atmosphere, affecting weather.
Fire doesn’t just consume trees and other plants. Fire interacts with other living things, like any other partner in the ecosystem. Plants come prepared with their adaptations, like the thick bark and limbless trunks of the mature pines, and the water-filled leaves of the succulents. Heat rising from a surface fire in a fuel-rich forest may kill all or most of the leaves and needles above without burning the tree. A tree whose vegetation is killed may die from the top down, its roots rotting until the skeleton is eventually toppled by wind.
A hot crown fire burns downward. If the burning ends at the lowest branches, a standing char – a blackened trunk – is left and may stand for decades. If the trunk keeps burning to the ground, the fire will follow the roots underground, until all the wood is consumed, leaving tunnels in the soil.
Like plants in the forest, animals are said to be adapted to wildfire, meaning they respond to warnings – smoke, the sounds of burning, the sight of flames – by fleeing or taking cover, taking advantage of natural refuges created by variations in landforms, water features, and vegetation. Birds fly away, reptiles hide underground. Some individuals may perish, but the population generally survives.
In the immediate aftermath of wildfire, we see loss, destruction, blackened skeletons, ground covered with ash. What we don’t see is potential new habitat prepared by the fire’s release of massive amounts of raw nutrients. An unhealthy excess of fuel buildup, purged. Unhealthy individuals and populations, cleansed. Fire-adapted roots and seeds, stimulated by fire and waiting, below the ash, for the next rain to sprout.
Many plants of our Southwestern forests are so well-adapted to wildfire that when their aboveground parts are completely consumed, they immediately and aggressively expand underground and re-sprout. Quaking aspen, gambel oak, and New Mexico locust respond this way, filling in burn scars with impenetrable thickets.
Burned agaves, including our narrow-leafed beargrass, immediately re-sprout from unburned root stock, along with ferns and mosses.
Nutrients released into the soil directly by wildfire, and later by the decomposition of fire-killed vegetation, encourage the growth of sprouts from the underground seed bank which is always present, waiting to take advantage of disturbances like fire.
When a stand of trees and other vegetation is killed and largely consumed by high-intensity wildfire, the ground that was held in place by roots is now vulnerable to erosion. When it rains after a fire, floods full of ash and sediment rush downstream. Like terrestrial plants and animals, fish and other aquatic organisms are fire-adapted and sense coming changes. Some are killed, but others take refuge or are washed downstream, to return later when conditions are right.
We think of erosion as merely loss of ground, but in nature, erosion opens new habitat, and floods and landslides move old rocks, soil, and dead vegetation downhill, where they’re eventually deposited to form more new habitat. Erosion can expose buried seeds. In general, erosion and deposition are a form of natural tilling – agitating, turning, and mixing the soil, releasing buried seeds and nutrients. Major erosional and depositional events, like I found in the Pinalenos, create new landforms, which themselves shape new habitats and microclimates of the living earth.
Wildfire releases new chemical nutrients directly, through the burning of soil, vegetation, and dead organic matter, but the process continues for decades after as organisms killed by the fire are consumed by decomposers like fungi, insects, and gut bacteria. The snags and char of fire-killed trees hold precious resources, the product of decades of hard work by the plant. Decomposers process these resources and make them available to the broader ecosystem.
The old notion of ecological succession says that, if environmental conditions – the fire regime – persist, the post-fire undergrowth and thickets will eventually be succeeded by some form of mixed-conifer forest, completing the fire cycle. Pine and fir seedlings will sprout from an existing seed bank, or from seeds carried by birds and buried by squirrels, and eventually grow to shade the shorter trees, which will die out, and you’ll end up with a replacement forest.
But now, with global climate change and massive, high-intensity wildfires, many forests are in danger of stand replacement and forest conversion. We’re told this is a bad thing, because forests help absorb the carbon emitted by our machines, protecting the earth from further climate change. But fire’s removal of the forest canopy opens light and space and liberates nutrients for lush forage – grasses and annuals, the foliage of deciduous shrubs and trees – attracting both herbivores and the predators that depend on them.
Patchy Burns, Biodiversity, and Mosaics
A decade ago when our big local wildfires started, and I anxiously followed the news, I was shocked and saddened by the scale of destruction that expanded daily, reaching hundreds of thousands of acres. Then, after a fire finally died down and damage surveys were reported, I was encouraged when authorities claimed only “patchy” damage.
It was only recently, during my weekly hikes in burn scars, that I began to understand. As described above, living fires tend to grow and move like amoebas, shaped by landforms, weather, and habitat. Even the most intense wildfire leaves patches of lower intensity and unburned habitat, so that the reported acreage of a large wildfire, measured by the outer boundary, is typically meaningless.
The giant Wallow Fire in Arizona’s White Mountains started at the southern edge of the range in the Bear Wallow Wilderness, where the high plateau is deeply dissected into ridges and canyons. So at its origin, the fire was diverted by terrain and missed large patches of forest. But when it reached Escudilla Mountain at the opposite, northeast end of the plateau – an ancient volcano with broad, rounded slopes of volcanic sediment that were not dissected by deep ravines – the fire found no barriers and engulfed the entire massif. Escudilla is older than the rest of the range. The modern fire’s growth and movement were determined by processes that formed the earth’s surface 20 to 40 million years ago.
There, and in similar terrain of New Mexico’s Mogollon Mountains and Black Range, wildfire completely eliminated mixed-conifer forest from entire slopes. Those mega-patches may recover slowly via natural succession, or they may be replaced by very different habitat.
What’s important – the potential for recovery – may be largely invisible, hidden underground. A moonscape may be replaced in only a few seasons by a stand of ferns and Gambel oaks. A formerly continuous stand of mixed-conifer forest will be replaced by a mosaic of forest, shrubland, and grassland.
The scientific study of patch dynamics theorizes that the smaller the patch, the less diverse. This would suggest that a continuous forest stand covering many square miles is much more diverse than the small patches of forest remaining after a patchy burn. But how can that be?
The original uniform mixed-conifer forest has been replaced by a mosaic of dramatically different patches: new grasslands, new shrublands, new eciduous forest, and remaining conifer forest. Each new patch can support a community that’s dramatically different from the original. And the proximity of different patches provides more opportunities for organisms that cross boundaries, like birds, herbivorous mammals, and their predators. Patch dynamics only studies plants, but plants are only one of the five kingdoms of life.
Southwestern forests may sometimes appear pristine because they lack the invasive plants which have taken over other Western habitat like deserts and overgrazed grasslands. But the forests we’ve known in our lifetimes are not natural. Before Europeans came and began suppressing wildfire, it’s likely that Southwestern forests were much more complex.
Adaptation and Resilience
Like habitat, adaptation is another word we understand poorly and use ambiguously, if at all. Biologists say plants and animals are adapted to particular environmental conditions, as a result of evolution. But that implies a passive, static, stable end state. In the traditional model of evolution, random genetic mutations make some individuals more successful than others, and those individuals thrive and produce successful offspring, while the less well-adapted die out.
European anthropocentrism has motivated an ongoing cultural effort to prove that humans are exceptional and qualitatively different from other animals. In the beginning, God gave us dominion over nature, but now, in a more secular society, we look for scientific evidence of our superiority to justify staying in charge. Some scientists say that our big brains represent a quantum leap in animal intelligence. While other animals are slaves to instinct, we alone possess consciousness and self-awareness, we alone are aware of our own mortality, we alone laugh, we alone think and reason, accumulate knowledge and wisdom, and pass it on to our offspring. We alone use tools, developed language and art, and so forth.
But in parallel, other scientists continue to debunk these Eurocentric misconceptions. Among humans, as among other animals, the vast majority of behavior is involuntary, driven by habit, not by reasoning or even by conscious intent. Our addiction to the groupthink of social media, in which peer groups reinforce unexamined beliefs, is a troubling reminder of this. We are typically no more aware of, or in control of, our behavior than a cow heading out to pasture.
But like us, other animals are capable of breaking their habits. Animals can observe, think, make decisions on the fly, learn, remember, and teach their offspring. Both animals and plants are often capable of migrating to new habitat when they lose theirs. This is not static adaptation, this is actively adapting in real time to disturbances, to changes in environmental conditions. And in line with conventional evolutionary theory, natural populations are provided with ongoing mutations that promote continuing, involuntary, unconscious adaptation of the species. Species in nature are not just adapted, they’re adaptable – or to use another newly fashionable term, they’re resilient.
A few years ago, after decades of fearing a takeover of desert riparian habitat by tamarisk, I stumbled upon a remote canyon where tamarisk had become established in some kind of surprising equilibrium with native plants. Very old tamarisk plants with trunks a foot in diameter stood isolated throughout the canyon, at respectful distances from traditional natives like seep willow and honey mesquite. All seemed stable and thriving, and I could see no new seedlings or spreading thickets of tamarisk. Maybe it was a freak of climate – maybe momentary conditions in the distant past had allowed the old invaders to get established, but subsequent conditions hadn’t enabled new seedlings. Or maybe it was a glimpse of the future.
We all seek stability. But in nature, catastrophic disturbances occur in cycles, and stability and sustainability always go hand in hand with change and adaptability. Plants and animals don’t expect to maintain the same conditions for their offspring in the future. They expect their offspring to be able to adapt to changing conditions.
Rising Temperatures and Drought
From year to year and season to season, higher temperatures and reduced precipitation cause whatever moisture is stored in living vegetation, dead organic matter, and soil to evaporate, resulting in drier and better fuel for wildfires. Prolonged heat and drought stress living plants, lowering their defenses against wildfire or killing them and adding to the fuel. We can all tell that climate changes during our lifetimes, from cool and wet years to hot and dry, back and forth, seemingly erratically. How do we sense when the effect of climate on our habitat puts it, and us, at risk?
People in traditional societies stayed in one place from generation to generation, accumulating and passing on long-term knowledge and wisdom about the local habitat they depended on for their livelihood, including long-term climate trends. But our hyper-mobile society pressures us to relocate over and over again, so we’ve lost that local, community-based perspective on climate. We’ve become dependent on news media and distant experts.
Weather forecasts can prepare us for local conditions during the next week, but to compete in the consumer economy, news media distract us with sensational events on a national or global scale, like a “polar vortex” producing mega-storms thousands of miles away, resulting in catastrophic urban damage and human suffering. Excepting those temporary system failures, our universal industrial infrastructure ensures that we’re largely independent of climate. No matter how hot and dry it gets, we can live in Phoenix or Las Vegas, keep ourselves cool with air conditioning, and turn on the tap to get water delivered from an invisible reservoir hundreds of miles away.
When I moved to California’s Bay Area in 1976, to attend grad school, I was told the region was in a drought. That was my first experience with drought, but since I didn’t know the region without drought, it didn’t really mean anything to me. The foothills behind the school greened up a little in winter, but spent the rest of the year covered with dead, tan-colored vegetation. Water still came out of the tap, and since I lived in an apartment, I didn’t have to worry about watering the lawn.
Eventually I learned that the California climate came in cycles. There were multi-year droughts, and then eventually there would be a wet winter or two. But civilization’s industrial infrastructure protected us and ensured that droughts caused little hardship – they were actually kind of fun. We could compete against each other to use less water and feel more righteous.
After falling in love with the Mojave Desert, I met scientists who told me that the desert, depending on the same winter storms as the coast, had its own cycle of multi-year droughts broken by wet winters. As I immersed myself in the desert’s regional climate, habitats, and ecosystems, I developed a sense of when the land was “hurting” from drought.
I also learned that, unlike back home on the coast, weather in the desert was highly localized. Precipitation totals from both winter and summer storms tended to be so low – only a few inches per year on average – that deviations of a quarter of an inch made a big difference.
The topographic relief of a mountain range compresses wind-driven air, “squeezing” rain or snow out of clouds, so that storms often form directly over mountains, and mountains tend to get much more precipitation from passing storms than valleys. But in the desert, each isolated mountain range, separated from its neighbors by miles of low basins, can receive widely differing amounts of precipitation, both from individual storms and throughout the year. One mountain range can be suffering while its neighbor is doing okay. When I call friends in the desert to ask about weather, they give me different reports on different mountains.
We approach our desert mountain wilderness on highways through broad basins at middle elevations, where the landscape is thinly carpeted with the delicate foliage of our iconic shrub, the creosote bush. The tiny, waxy leaves glow a vibrant green when it has enough water, but shrivel and take on a more muted brownish tint in drought, and we desert lovers can tell that from a distance, at a glance.
Our first destination is usually a natural water source – a more or less perennial spring or seep. We know the amount of water present on the surface is directly dependent on annual precipitation. Living through both summer cloudbursts and winter storms from the Pacific, I learned that it’s the long soaking rains of winter that restore life. Water from summer cloudbursts quickly flushes downhill, evaporating along the way. A long, steady winter rain is absorbed by soils, plants, and fracture zones in the rock, where the water may be released slowly at natural springs and seeps for use by wildlife during coming seasons.
During the four decades I’ve been exploring the desert, more and more water sources I assumed to be perennial have dried up. Drought is deepening, and wildfires will be more destructive.
Scientists collect data with their instruments – thermometers, hygrometers, rain gauges, etc. – store the data in databases over time, and analyze it to measure climate change in specific regions. But weather stations are rare in the desert. There’s none in the entire mountain range where my land is located, so there’s no data – either current or historical – on temperature or precipitation there.
Field biologists try to detect the local impacts of climate change via surveys of plant and animal populations, sampling and analyzing, for example, seed germination rates, nutrient value of forage at peak times, survival rates of offspring, and mortality rates per population. Climate stress may also be inferred from secondary impacts like disease, parasitism, and of course wildfire.
My new home in southwest New Mexico has a distinct regional climate regime, depending equally on winter storms and summer monsoons, whose moisture comes from the Pacific Ocean and the Gulf of California. Old-timers spoke of the monsoon starting like clockwork after the 4th of July, but in my first year, it didn’t start until the end of the month, and it’s never been dependable since. Sometimes it barely comes at all. We don’t talk about drought as much as about a “good” or a “poor” monsoon, and a wet or dry winter. After 15 years, I seem to remember only two or three good monsoons, but those remain my definition of our climate.
A neighbor who grew up here told me they used to regularly get 16″ of snow in a winter storm, but since I moved here fifteen years ago, we’ve never had more than 8″ in town. I haven’t measured or kept records on temperature, rainfall, or snow accumulation, but the past few winters have seemed unusually warm and dry, and monsoons have been poor.
Whereas the monsoon is our iconic season, it’s the winter snows that restore our mountain forests. In the cooler climate of our region’s past, snow accumulated at high elevation throughout the winter, then melted slowly in March and April. This allowed soil, dead organic matter, and living plants to soak up the moisture. Now, in a warming climate, when snow falls, it quickly melts and moisture runs off before the system can absorb and store it. In the dry and windy season that follows, wildfire is provided with more and better fuel.
Our mobility has robbed us of the local experience and wisdom that could help us judge what’s happening, while media distract us with images of distant disasters and experts warn of global processes too complex and abstract to be locally useful. We’re left with generalized anxiety about climate, and a desperate hope that the authorities will protect us.
We civilized humans may accept that climate is changing, but unlike animals, we’re not adaptable – we’re not resilient. Despite abundant evidence that our societies are conflicted and dysfunctional, we cling to the irrational hope that our leaders will fine-tune our vast industrial infrastructure, so we and our children can continue to enjoy the same standard of living, jumping on a freeway to visit family or shop at a distant store, running air conditioners in Phoenix, turning a faucet to get water from a distant reservoir. Meanwhile, out of sight and out of mind to most of us, that infrastructure destroys more natural habitat and sparks more wildfires.
Beauty of Wildfire
Everyone in the American West has overdosed on TV footage of wildfire, usually shot from the air at night, and from that, we may imagine we know and understand wildfire. But the fire cycle has a complex and often subtle beauty that’s not limited to the momentary apocalyptic vision of flames burning at night.
Next: Government and Wildfire
Very interesting. So much information and a different way of looking at ecology/environment/change and growth. Thank you.