Bootleg Fire in Oregon is too large and hot to contain

From an Article by Sarah Kaplan, Washington Post, July 1, 2021

Heat waves have toppled temperature records across the nation, and firefighters are actively battling 48 large blazes that have consumed more than half a million acres in 12 states. But land management agencies are carrying out fire mitigation measures at a fraction of the pace required, and the funds needed to make communities more resilient are one-seventh of what the government has supplied.

“We’re burning up, we’re choking up, we aren’t just heating up,” California Gov. Gavin Newsom (D) told President Biden at a meeting with Cabinet officials and Western governors Wednesday. “Across the board we have to disabuse ourselves of the old timelines and the old frames of engagement. … We can’t just double down.”

Yet fire experts say the escalation of wildfires, fueled by climate change, demands an equally dramatic transformation in the nation’s response — from revamping the federal firefighting workforce to the management of public lands to the siting and construction of homes.

“As our seasons are getting worse and worse … it feels like we’ve reached a tipping point,” said Kelly Martin, a wildfire veteran and president of the advocacy group Grassroots Wildland Firefighters. “We need a new approach.”

The West’s hot, dry start to summer has already been devastating, to people as well as trees.

On Thursday, authorities across the Pacific Northwest and western Canada said they were investigating at least 500 suspected deaths from heat illness that occurred amid the week’s record-shattering temperatures.

Thousands of residents had to be rapidly evacuated from the sprawling Lava Fire, south of the Oregon-California border, when extreme heat and strong winds caused the blaze to explode.

Many people are still missing after a fast-moving wildfire overwhelmed the tiny mountain village of Lytton, British Columbia, on Wednesday — just a day after it notched Canada’s highest-ever temperature of 121 degrees Fahrenheit.

“This is becoming a regular cycle, and we know it’s getting worse,” Biden said Wednesday. “In fact, the threat of Western wildfires this year is as severe as it’s ever been.”

‘Always doing more with less’

When Martin started her career with the U.S. Forest Service more than three decades ago, the agency had a “warlike” approach to handling wildfires. Crews used bulldozers and other equipment to cut through vegetation and create barriers that could contain an approaching front. Helicopters and big air tankers dropped retardant from high above the flames. Although land managers knew fire was an important part of most Western ecosystems, they were also under pressure to stop blazes before they reached the area’s growing population centers.

“And we were very successful at it,” Martin said. To this day, more than 95 percent of fires are suppressed before they reach communities.

But by the time Martin retired as chief of fire and aviation at Yosemite National Park last year, climate change had fundamentally altered the nature of wildfire, making the blazes that did escape containment increasingly costly and dangerous to fight.

In most forest types, the proportion of fires that are “high severity” (killing the majority of vegetation) has at least doubled in recent decades. Firefighters are seeing more and more “extreme fire behavior” — whirling “fire tornadoes,” crown fires that spew embers into the wind and blazes that move so fast and burn so hot they create their own weather.

In 2018, a veteran Redding, Calif., firefighter was killed when a vortex the size of several football fields swept down upon him as he evacuated residents ahead of the catastrophic Carr Fire.

“Watching what the current wildland firefighters are faced with, last year and this year, it is exponentially greater in terms of risk and trauma,” Martin said.

The U.S. government is the nation’s biggest employer of what are known as “wildland” firefighters. Most are temporary workers, their salaries as low as $13.45 per hour for a starting forestry technician. They spend summers traveling the country, working 16-hour days, 12 days at a time, often relying on overtime and hazard pay to make ends meet.

For decades, they’ve relied on a months-long offseason to rest and recover.

But now there is no offseason; one fire year simply bleeds into the next, as winter rain and snow is delayed and diminished by climate change. About 100 families had to be evacuated from the Santa Cruz mountains in January — usually California’s wettest month — when winds re-ignited the embers of a fire that started last August.

Earthquakes above magnitude 3 out of control (USGS)

From an Article by Emily Brodsky, The Conversation, September 2, 2018

Earthquakes in the central and eastern U.S. have increased dramatically in the last decade as a result of human activities. Enhanced oil recovery techniques, including dewatering and hydraulic fracturing, or fracking, have made accessible large quantities of oil and gas previously trapped underground, but often result in a glut of contaminated wastewater as a byproduct.

Energy companies frequently inject wastewater deep underground to avoid polluting drinking water sources. This process is responsible for a surge of earthquakes in Oklahoma and other regions.

The timing of these earthquakes makes it clear that they are linked with deep wastewater injection. But earthquake scientists like me want to anticipate how far from injection sites these quakes may occur.

In collaboration with a researcher in my group, Thomas Goebel, I examined injection wells around the world to determine how the number of earthquakes changed with the distance from injection. We found that in some cases wells could trigger earthquakes up to 10 kilometers (6 miles) away. We also found that, contradictory to conventional wisdom, injecting fluids into sedimentary rock rather than the harder underlying rock often generates larger and more distant earthquakes.

Transmitting Pressure Through Rock

Assessing how far from a well earthquakes might occur has practical consequences for regulation and management. At first glance, one might expect that the most likely place for wastewater disposal to trigger an earthquake is at the site of the injection well, but this is not necessarily true.

Since the 1970s, scientists and engineers have understood that injecting water directly into faults can jack the faults open, making it easier for them to slide in an earthquake. More recently it has become clear that water injection can also cause earthquakes in other ways.

For example, water injected underground can create pressure that deforms the surrounding rock and pushes faults toward slipping in earthquakes. This effect is called poroelasticity. Because water does not need to be injected directly into the fault to generate earthquakes via poroelasticity, it can trigger them far away from the injection well.

Deep disposal wells are typically less than a foot in diameter, so the chance of any individual well intersecting a fault that is ready to have an earthquake is quite small. But at greater distances from the well, the number of faults that are affected rises, increasing the chance of encountering a fault that can be triggered.

Of course, the pressure that a well exerts also decreases with distance. There is a trade-off between decreasing effects from the well and increasing chances of triggering a fault. As a result, it is not obvious how far earthquakes may occur from injection wells.

Where to Inject?

To assess this question, we examined sites around around the world that were well-isolated from other injection sites, so that earthquakes could clearly be associated with a specific well and project. We focused on around 20 sites that had publicly accessible, high-quality data, including accurate earthquake locations.

We found that these sites fell into two categories, depending on the injection strategy used. For context, oil and gas deposits form in basins. As layers of sediments gradually accumulate, any organic materials trapped in these layers are compressed, heated and eventually converted into fossil fuels. Energy companies may inject wastewater either into the sedimentary rocks that fill oil and gas basins, or into older, harder underlying basement rock.

At sites we examined, injecting water into sedimentary rocks generated a gradually decaying cloud of seismicity out to great distances. In contrast, injecting water into basement rock generated a compact swarm of earthquakes within a kilometer of the disposal site. The larger earthquakes produced in these cases were smaller than those produced in sedimentary rock.

This was a huge surprise. The conventional wisdom is that injecting fluids into basement rock is more dangerous than injecting into sedimentary rock because the largest faults, which potentially can make the most damaging earthquakes, are in the basement. Mitigation strategies around the world are premised on this idea, but our data showed the opposite.

How wastewater injection can make earthquakes: In basement rocks (left), injection activates faults in the small region directly connected to the added water, shown in blue. In sedimentary injection, an additional halo of squeezed rock, surrounds the pressurized fluid and can activate more distant faults.

Why would injecting fluids into sedimentary rock cause larger quakes? We believe a key factor is that at sedimentary injection sites, rocks are softer and easier to pressurize through water injection. Because this effect can extend a great distance from the wells, the chances of hitting a large fault are greater. Poroelasticity appears to be generating earthquakes in the basement even when water is injected into overlying sedimentary rocks.

In fact, most of the earthquakes that we studied occurred in the basement, even at sedimentary injection sites. Both sedimentary and basement injection activate the deep, more dangerous faults – and sedimentary sequences activate more of them.

Although it is theoretically possible that water could be transported to the basement through fractures, this would have to happen very fast to explain the rapid observed rise in earthquake rates at the observed distances from injection wells. Poroelasticity appears to be a more likely process.

Avoiding Human-Induced Quakes

Our findings suggest that injection into sedimentary rocks is more dangerous than injecting water into basement rock, but this conclusion needs to be taken with a rather large grain of salt. If a well is placed at random on Earth’s surface, the fact that sedimentary injection can affect large areas will increase the likelihood of a big earthquake.

However, wells are seldom placed at random. In order to efficiently dispose of wastewater, wells must be in permeable rock where the water can flow away from the well. Basement rocks are generally low permeability and therefore are not very efficient areas in which to dispose of wastewater.

One of the few ways that basement rocks can have high permeability is when there are faults that fracture the rock. But, of course, if these high permeability faults are used for injection, the chances of having an earthquake skyrocket. Ideally, injection into basement rock should be planned to avoid known larger faults.

If a well does inject directly into a basement fault, an anomalously large earthquake can occur. The magnitude 5.4 Pohang earthquake in South Korea in 2017 occurred near a geothermal energy site where hydraulic injection had recently been carried out.

The important insight of this study is that injection into sedimentary rocks activates more of these basement rocks than even direct injection. Sedimentary rock injection is not a safer alternative to basement injection.