Climate research: How the Greenland ice sheet can still be saved

by Technical University Munich

Time series of ice volume and spatial extents of the GrIS for warming scenarios without

 mitigation. a, Sketch of applied warming and cooling scenarios in this study. The warming 

period lasts for 100 years, followed by varying cooling phases. The black line corresponds 

to scenarios without mitigation as shown in this figure. b, Evolution of total GrIS ice volume

 simulated by PISM-dEBM, without reversal of the temperature anomalies (black line in 

panel a), for different temperature anomalies between ΔTJJA = 0 °C and 7.0 °C above 

present. The warming period lasts for 100 years until year ad 2100 and temperatures are

 kept constant afterwards. Three qualitatively different regimes are noticeable: 

(1) present-day configuration with fully extended ice sheet or only slightly reduced volume;

 (2) intermediate state with around 75% of present-day ice volume; and (3) basically ice-free

 states. The vertical black line at 5 kyr denotes a change of the x-axis scaling for visual

 clarity. We normalize the ice volumes to the observed present-day values 

(see Methods sections ‘PISM-dEBM’ and ‘Yelmo-REMBO’). c, Ice thickness of present-day

 ice-sheet configuration in PISM-dEBM. The ice sheet is fully extended. d, Same as c but

 the intermediate state for ΔTconv,JJA = 2.0 °C, after 100,000 years with PISM-dEBM. The

 southwestern part of the ice sheet is fully retracted. e, Same as c but for the ice-free state

 with PISM-dEBM. f,g,h, Same as b,c,e, respectively, but for Yelmo-REMBO. Only two 

regimes can be identified: (1) present-day configuration; and (2) near-ice-free states. 

The maps were made with the Python package cartopy52 and Natural Earth. 

Credit: Nature (2023). DOI: 10.1038/s41586-023-06503-9

Greenland is the second largest permanently ice-covered surface on the Earth; only Antarctica is larger. The Greenland ice sheet is drastically impacted by the effects of climate change. If the ice sheet melts completely it would cause a sea level rise of more than seven meters—a catastrophe for coastal regions worldwide and for the people who live there.

The critical threshold for the worst-case scenario is between 1.7 and 2.3 degrees Celsius of global warming above the preindustrial level on an annual average. Until now climate research has assumed that if this point is exceeded, the Greenland ice sheet would be lost forever. However, the international research team has now been able to show in a large set of simulations that there would be a way back after passing the tipping point.

Irreversible damage to the ice sheet are avoidable

Niklas Boers is Professor of Earth System Modeling at TUM and member of the Potsdam Institute for Climate Impact Research (PIK). Together with scientists from UiT The Arctic University of Tromsø and the Complutense University of Madrid, he has succeeded in proving that the tipping point for the Greenland ice sheet can temporarily be exceeded without irreversible damage.

"Our simulations have shown us that it is possible to stop the melting of Greenland's ice sheet in spite of failure to meet climate goals and to even reverse the process. Here the important thing is that if the tipping point is exceeded, massive countermeasures would be necessary and the Earth would have to be cooled down to below the critical values," says Prof. Niklas Boers.

No green light for 'more business as usual'

However, the new findings do not mean that society can be satisfied with its climate protection achievements to date; instead the findings are to be seen much more as a second chance and an outlook for the future. In the simulation the researchers used two different ice sheet models. A large number of scenarios were run, with global warming between 1.5 and 6.5 degrees Celsius until 2100 and a subsequent cooling phase of between 100 to 10,000 years.

"Using super-computers we were able to calculate this enormous number of scenarios reaching 100,000 years into the future so that we could be completely certain that the Greenland ice sheet is in balance. However, in both ice sheet models we were able to show that the ice sheet can recover, as long as the critical temperature threshold value is only exceeded for a limited period of time of several centuries," says Nils Bochow, scientist at UiT and also member of PIK.

Recovery possible, but only with concerted action

The prerequisite for recovery of the ice sheet is the prompt correction of the temperature on the Earth in a time frame of about 500 years, depending on how far the maximum temperatures rise above the critical values. The speed, drastic nature, effort and expense of the countermeasures necessary for cooling the Earth will increase with the time the tipping point is exceeded and the increase in temperature during that time.

Drastic measures include massive reduction in atmospheric CO2 concentrations on the entire planet and thereby reducing global temperatures, using technologies like wide-scale re- and aforestation and carbon capture and storage. The scientists' calculations indicate that countermeasures will not have to be as extreme if global warming only slightly exceeds the targets defined in the Paris Climate Accord. The new findings are thus a sign of hope in the search for a way to stop climate change before our last chance is gone.

The work is published in the journal Nature.

More information: Nils Bochow, Overshooting the critical threshold for the Greenland ice sheet, Nature (2023). DOI: 10.1038/s41586-023-06503-9. www.nature.com/articles/s41586-023-06503-9

Journal information: Nature 

Provided by Technical University Munich The Greenland Ice Sheet is close to a melting point of no return, says new study

 

Drought in the Amazon: Understanding the causes and the need for an immediate action plan to save the biome

by Lucas Ferrante, The Conversation

Credit: Pixabay/CC0 Public Domain

The drought plaguing the Amazon is a worrying portrait of the climate challenges facing the world. The combination of the El Niño phenomenon and anthropogenic climate change has played a significant role in accentuating this extreme weather event. The Amazon region, known for its lush rainforest and flowing rivers, is facing a critical situation due to a lack of rainfall and rising temperatures.

This phenomenon, never recorded at this intensity, has affected biodiversity and human life in eight Amazonian states. The drought has already killed more than 140 dolphins, including pink dolphins and tucuxis, also known as gray dolphins. The mortality of fish and other aquatic animals is also high.

The low volume of the rivers affects the human supply, causing a lack of drinking water and food in all the small villages, even those located on the banks of the big rivers. Of the 62 municipalities in the state of Amazonas, 42 are in a state of emergency, 18 are in a state of alert and only two are in a normal situation.

The El Niño phenomenon has a direct influence on the Amazon drought. It manifests itself in the abnormal warming of the surface waters of the Pacific Ocean, affecting the rainfall regime in various parts of the world. In the case of the Amazon region, the drought is exacerbated by a decrease in humidity and a lack of rainfall, damaging the vegetation, fauna and local communities that depend on natural resources.

However, anthropogenic climate change is making the situation even worse. Rampant deforestation, driven by agricultural expansion and logging activity, reduces the Amazon rainforest's ability to regulate the climate and retain moisture. In addition, the destruction of vast areas of vegetation contributes to rising temperatures, creating a cycle of even more accentuated droughts.

Deforestation and mining, major factors

Deforestation has been particularly devastating in the region of Highway BR-319, in the south of Amazonas state, driven by land grabbing which has provided cheap land to cattle ranchers from other states. In turn, this deforestation has increased the number of fires that feed back into the climate crisis. When they occur near riverbanks, deforestation also intensifies the phenomenon known as fallen land, which has drastically affected the draft of rivers and is already significantly jeopardizing navigation and logistics, mainly affecting villages in the interior of the Amazon, which are already suffering from shortages.

Another factor that has played a significant role in affecting navigation is mining activity. Disorganized mineral extraction has created banks of land that are harmful to navigation and which, in the critical scenario of drought, have caused many vessels to run aground.

The impact of hydroelectric dams

Hydroelectric dams also play a role in contributing to the drought scenario, especially on the Madeira River. This is mainly due to the decomposition of organic matter in reservoirs created by dams, which releases methane, a potent greenhouse gas, into the atmosphere. In addition, deforestation associated with the construction of dams, as well as soil degradation and erosion resulting from the alteration of aquatic and terrestrial ecosystems, can increase emissions of carbon dioxide (CO2) and other pollutants, contributing to the impact of hydroelectric dams on climate change.

The Madeira River, now at its lowest level in almost 60 years, has been drastically affected and transformed by the Jirau and Santo Antônio hydroelectric dams. This was due to the drastic alteration of the river's natural flow caused by the damming of water for power generation. When water is dammed, a reservoir is formed that retains part of the water that would normally flow along the river. This diversion of the flow directly affects the region's aquatic and terrestrial ecosystems, since the basin's hydrological cycle is interrupted. The reduction in the volume of water in the Madeira River, for example, can lead to prolonged periods of drought, affecting not only aquatic fauna and riparian habitats, but also local communities that depend on the river for their livelihoods.

In addition, the construction and operation of hydroelectric dams in the Amazon often involves the clearing of significant areas of forest for the construction of dams and associated infrastructure. Deforestation contributes to a reduction in evapotranspiration, which is a crucial process for water balance in the region. With fewer trees to release water into the atmosphere, the Amazon becomes more susceptible to drought. The combination of these factors results in a significant impact on the region, making hydroelectric dams one of the causes of drought in the Amazon, particularly on the Madeira River, with worrying environmental and social consequences.

What can still be done

In order to combat the extreme drought in the Amazon and its devastating effects, it is essential to adopt strict measures to curb deforestation and illegal mining in the region, and for the federal government to review major undertakings such as hydroelectric dams and roads, such as the BR-319 motorway.

Many politicians have argued that the road, if paved, could reduce the state's isolation, especially during droughts. However, this is a fallacious argument, because connecting the most isolated municipalities would require hundreds of kilometers of side roads, which would further increase deforestation and aggravate the climate crisis.

In addition, the BR-319 motorway has become a spearhead that cuts through one of the most conserved blocks of forest, linking the central Amazon, which is still preserved, to the "arc of Amazonian deforestation", a region that concentrates most of the climate anomalies in the entire biome.

Ecosystem on the edge

In a recent study published in the journal Conservation Biology, it was shown that deforestation in the Amazon is already impacting ecosystem services that are essential for Brazil, such as the Amazon's flying rivers. This scientific data shows that we are already at the threshold of deforestation and environmental degradation tolerated by the Amazon, and more forceful action needs to be taken now.

Part of this responsibility lies now in the hands of President Lula, in reviewing major developments in the Amazon, such as hydroelectric dams and highways like the BR-319. In addition, it is essential to institute a zero deforestation policy that should begin this year, and not in 2030, when it will be too late. Furthermore, it is crucial that the international community and local governments work together to reduce greenhouse gas emissions and tackle climate change effectively. Only with coordinated and decisive action will we be able to mitigate the impacts of drought in the Amazon and protect this unique ecosystem that plays a vital role in regulating the global climate.

Journal information: Conservation Biology 

Provided by The Conversation 

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Deforestation down in Brazil's Amazon

 

Researchers: Slow solutions to fast-moving ecological crises won't work—changing basic human behaviors must come first

by Mike Joy and Phoebe Barnard, The Conversation

Credit: Pixabay/CC0 Public Domain

As the world grapples with multiple ecological crises, it's clear the various responses over the past half century have largely failed. Our new research argues the priority now should be addressing the real driver of these crises—our own maladaptive behaviors.

For at least five decades, scientists have worked to understand and document how human demands exceed Earth's regenerative capacity, causing "ecological overshoot".

Those warnings of the threats posed by the overshoot's many symptoms, including climate change, were perhaps naive. They assumed people and governments would respond logically to existential threats by drastically changing behaviors.

The young researchers in the 1970s who published the Limits to Growth computer models showed graphically what would happen over the next century if business-as-usual economic growth continued. Their models predicted the ecological and social disasters we are witnessing now.

Once people saw the results of the research, the authors believed, they would understand the trajectory the world was on and reduce consumption accordingly. Instead, they saw their work dismissed and business-as-usual play out.

The behavioral crisis

During these past five decades, there have been innumerable reports, speeches and data, ever more strident in their predictions. Yet there has been no change in the economic growth trajectory.

The first world scientists' warning to humanity was published in 1992 as an open letter, signed by hundreds of scientists and detailing how human activities damage the environment. A second notice in 2017, which thousands of scientists signed, included this stark statement: "If the world doesn't act soon, there will be catastrophic biodiversity loss and untold amounts of human misery."

Many of those working in the natural sciences felt they were doing what they could to prevent this "ghastly future" unfolding. Researchers even laid out a framework of actions for the world to take, including human population planning and diminishing per-capita consumption of fossil fuels, meat and other resources. But few meaningful changes have been achieved.

By taking a different perspective, our research explores intervention points and demonstrates the behavioral roots of ecological overshoot. It is a collaboration with behavior-change strategists in the marketing industry, and grew partly from their disaffection with the outcomes of their work on human and planetary health.

Behind the research sits a stark statistic: the wealthiest 16% of humanity is responsible for 74% of excess energy and material use. This reflects a crisis of human behavior. It is the outcome of many individual choices involving resource acquisition, wastefulness and accumulation of wealth and status.

Some of these choices may have served humans well in the evolutionary past. In a modern global economy, however, they become maladaptive behaviors that threaten all complex life on Earth.

The 'growth delusion'

Current interventions to restrain climate change—just one symptom of ecological overshoot—are failing to curb emissions. Last year, global emissions of carbon dioxide reached a new high, partly as a result of air travel rebounding after the COVID pandemic.

We argue that trying to fix an accelerating problem with slow solutions is itself the problem. Instead, we need to treat the root causes of ecological overshoot and its behavioral drivers, rather than be distracted by patching up its many symptoms.

A prime example is the current "solution" to climate change through a full transition to renewable energy systems. This simply replaces one form of energy with another, but doesn't address the rising demand for energy that enabled overshoot in the first place.

Such interventions are incremental, resource intensive, slow moving and flawed: they aim to maintain rather than manage current levels of consumption. This "growth delusion" offers a false hope that technology will allow human society to avoid the need for change.

An emergency response

To overcome the critical disconnect between science, the economy and public understanding of these issues, an interdisciplinary response will be needed.

Paradoxically, the marketing, media and entertainment industries—central to the manipulation of human behaviors towards resource acquisition and waste—may offer the best way to reorient that behavior and help avoid ecological collapse.

Logically, the same behavioral strategies that fueled consumerism can do the reverse and create the necessary desire for a stable state.

Understanding the many dimensions of the behavioral crisis, including the influence of power structures and vested interests in a market economy, is crucial. Defusing and even co-opting those forces to reform the economy and reverse the damage is the challenge.

It will require a concerted multi-disciplinary effort to identify the best ways to produce a rapid global adoption of new norms for consumption, reproduction and waste. The survival of complex life on Earth is the goal.

Provided by The Conversation 

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Critics of 'degrowth' economics say it's unworkable—but from an ecologist's perspective, it's inevitable

 

How NASA's Europa Clipper will survive its trip to Jupiter's hostile moon

by Gina Errico, Los Angeles Times

Credit: Kevin Gill from Nashua, NH, United States, CC BY-SA 2.0 , via Wikimedia Commons

If life exists elsewhere in the solar system, it may well reside in the ocean of Jupiter's icy moon Europa.

The mysterious world appears to have the necessary ingredients for life as we know it. Beneath its frozen exterior is a single body of water that's so deep it may hold more liquid than all of the oceans on Earth. Europa is believed to have enough carbon, hydrogen, nitrogen, oxygen and other key elements to form the building blocks of living organisms. And scientists suspect the heat generated as the moon is stretched and squeezed by Jupiter's gravity would provide enough energy to sustain any creatures that might be there.

That's why NASA is building Europa Clipper.

The spacecraft will blast off from the Kennedy Space Center in Florida a year from now and reach its destination in 2030. Once there, it will perform dozens of flybys so its nine dedicated instruments can learn more about Europa's geology and determine whether it is indeed hospitable to life.

"The ocean makes it one of the best places to look for habitability," said Cynthia Phillips, a planetary geologist at the Jet Propulsion Laboratory in La Cañada Flintridge and project staff scientist for the $5-billion Europa Clipper mission.

But there's one major obstacle: Jupiter is home to the harshest known radiation belts in the solar system. The radiation exposure is so high that a person visiting Europa would receive a lethal dose in a matter of hours, according to the European Space Agency. Europa's delicate instruments are a little hardier than a human, but not by much.

That's why NASA scientists and engineers designed a complex flight path for the spacecraft, with elliptical orbits that will keep it a safe distance from Jupiter's radiation belts as much as possible. Only one or two days out of Europa Clipper's two- to three-week orbits will be spent in the most intense radiation zone, dipping in to gather an array of data before retreating to recover.

"On each flyby, it's like holding your breath," Phillips said. The spacecraft "will take a deep breath, go in and take all of the pictures and observations, and then get out of there." Then it will have a week or two to recuperate while the scientists back on Earth examine the data and come up with new commands for the next flyby, she said.

The goal is to execute 45 runs over 2½ years, coming within 16 miles of Europa's surface. At that distance, Clipper's magnetometer will be able to measure the depth and salinity of the moon's ocean; its mass spectrometer will study the ocean's chemical makeup; and its ultraviolet spectrograph will search for plumes of water vapor escaping through the icy shell.

But even quick flybys aren't enough to protect the spacecraft's suite of instruments from Jupiter's tough radiation environment. So they'll be encased in custom-made aluminum armor that's about 1 centimeter thick.

Being bombarded with the high-energy particles that make up Jupiter's radiation belts is like sitting under an aluminum roof in a hailstorm—it may protect you for a while, but eventually it will sustain too too much damage to do its job.

So JPL engineers didn't try to make armor to deflect the radiation. Instead, they developed a material that absorbs the particles zooming toward the spacecraft and diverts them away from its sensitive interior, protecting both the instruments and any data they've collected, said Insoo Jun, co-chair of the Clipper Radiation Focus Group and a member of the Europa Clipper science team.

Scientists have wanted to get a close look at Europa since the early 1970s, when images from a telescope at Kitt Peak National Observatory in Tucson revealed that the moon's surface was made of water ice. Visits by NASA's Voyager 1 and Voyager 2 spacecraft in 1979 suggested the moon was active, and the Galileo mission in 1995 confirmed that Europa had a subsurface ocean, as some scientific models predicted.

Speculation about Europa's potential habitability also got a boost from a discovery on Earth—an array of unexpected organisms living near magma-fueled hydrothermal vents on the ocean floor.

The data Europa Clipper collects will help scientists determine whether the icy moon really is the prime exobiology candidate they think that it may be.

"This mission is challenging," Phillips said. "Europa is key to understanding not just the habitability of our own solar system, but potentially expanding the definition of the habitable zone."

Traditionally, the habitable zone has been thought of as the region around a star where a planet gets the right amount of energy to keep water in liquid form on its surface. Europa is too far away to get that energy from the Sun, but perhaps the push and pull of Jupiter's gravity can provide it instead.

"If there are habitable environments on Europa," Phillips said, "that could have profound implications for the probability of life in the cosmos."

2023 Los Angeles Times.

New video series captures team working on NASA's Europa Clipper

 

NASA's Psyche asteroid mission: A 3.6 billion kilometer 'journey to the center of the Earth'

by Hrvoje Tkalčić, The Conversation

Credit: NASA / JPL-Caltech / ASU

Psyche was the Greek goddess of the soul, born a mere mortal and later married to Eros, the God of love. Who knows why the Italian astronomer Annibale de Gasparis gave her name to a celestial object he observed one night in 1852?

Psyche was only the 16th "asteroid" ever discovered: inhabitants of the solar system that were neither the familiar planets nor the occasional visitors known as comets. Today we know the asteroid belt between the orbits of Mars and Jupiter contains millions of space rocks, ranging in size from the dwarf planet Ceres down to tiny pebbles and grains of dust.

Among all these, Psyche is still special. With an average diameter of around 226km, the potato-shaped planetoid is the largest "M-type" asteroid, made largely of iron and nickel, much like Earth's core.

Last week NASA launched a spacecraft to rendezvous with Psyche. The mission will take a six-year, 3.6 billion kilometer journey to gather clues that Earth scientists like me will interrogate for information about the inaccessible interior of our own world.

Natural laboratories

M-type asteroids like Psyche are thought to be the remnants of planets destroyed in the early years of the solar system. In these asteroids, heavier elements (like metals) sank toward the center and lighter elements floated up to the outer layers. Then, due to collisions with other objects, the outer layers were torn away and most of the material was ejected into space, leaving behind the metal-rich core.

These metallic worlds are perfect "natural laboratories" for studying planetary cores.

Our current methods for studying Earth's core are quite indirect. We sometimes get tiny glimpses into the solar system's early history—and hence our planet's own history—from metallic meteorites, parts of asteroids that fall to Earth. However, this view is very limited.

Another way to study the core is using seismology: studying how the vibrations caused by earthquakes travel through the planet's interior, in much the same way doctors can use ultrasound to see the inside of our bodies.

However, on Earth we have fewer seismographs in the oceans and in the Southern Hemisphere, which restrict what we can see of the core.

What's more, the core is buried beneath the planet's outer layers, which obscure our view even further. It is like looking at a distant object through an imperfect lens.

As well as seismology, we learn about the core through lab experiments attempting to recreate the high pressures and temperatures of Earth's interior.

We take the observations from seismology and lab experiments and try to explain them using computer simulations. In a recent paper in Nature Communications, we discussed the current challenges in studying Earth's core—and the ways forward.

What the Psyche mission hopes to discover

We can think of NASA's mission to Psyche as a journey to the center of Earth without having to travel down through the planet's rocky crust, the slowly moving mantle and the liquid core.

The mission aims to find out whether Psyche really is the core of a destroyed planet, that was initially hot and molten but slowly cooled and solidified like the core of our planet. On the other hand it's possible Psyche is made of material that was never melted at all.

NASA also wants to discover how old Psyche's surface is, which would reveal how long ago it lost its outer layers. The mission will also investigate the asteroid's chemical composition: whether it contains lighter elements alongside iron and nickel, such as oxygen, hydrogen, carbon, silicon and sulfur. The presence or absence of these could give us clues about our own planet's evolution.

Information about Psyche's shape, mass, and gravity distribution will also be gathered. Also, the potential for future mineral exploration should be studied.

All of this will be possible with the broad-spectrum cameras, spectrometers, magnetometers, gravimeters and other instruments the spacecraft carries. Scientists like me will follow with impatience the mission's long journey through space.

Provided by The Conversation 

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Scientists use Webb, SOFIA telescopes to observe metallic asteroid

 

Study shows need for ITU to tighten regulations for low orbit satellites as filing numbers grow

by Bob Yirka , Phys.org

Credit: Pixabay/CC0 Public Domain

A small team of political scientists and astronomers at the University of British Columbia has conducted a study of the number of filings to the International Telecommunication Union (ITU) by entities wishing to send satellites into low orbit and has found the numbers growing so fast that soon there will not be room for new satellite deployments. In their paper is published in the journal Science.

Satellites designed for use in communications systems must be put into low Earth orbit—most of them are used for internet services. But those wishing to deploy them must file for orbital space with the ITU, a United Nations entity that has been tasked with regulating Earth orbital space.

In recent years, large entities such as Starlink have filed for multiple orbital space slots in large bunches; such slots are used by multiple small satellites that together comprise a constellation. These are needed because the satellites are deployed in a geosynchronous orbit, which means multiple satellites are needed to create networks over large geographical areas, such as countries.

Prior research has shown that as more satellites are launched into low orbit, the belt around the planet becomes more crowded—eventually, there will no longer be room for any new satellites. In response, many entities such as Starlink have begun overfiling—filing requests for satellites that have not even been built yet. And some, like Starlink, have attempted to skirt the system by making multiple filings from different countries.

In this new effort, the researchers analyzed the ITU database and found that filing requests are on a path that will choke the system. They found, for example, that there are currently filings in place that represent approximately 1 million new satellites, which includes plans for deploying 300 mega-constellations. They note that such figures represent a 115% increase over current low-orbit traffic. Such large numbers of satellites, they note, need to be better regulated to prevent collisions and to find the eventual cut-off point.

The researchers also found entities filing for more orbital slots than they currently need, as insurance against future needs. And they found many filings that are not likely to result in satellite deployments at all due to funding, political or other issues.

The research team suggests that participants at this year's ITU meeting (next month) begin looking at adding more regulations regarding filings to prevent entities from overfilling and to remove those that do not belong. They also note that rules could be enacted regarding how long a filing remains in the database, and perhaps instigating a system of bonds that can be redeemed when an entity removes a satellite from low orbit.

More information: Andrew Falle et al, One million (paper) satellites, Science (2023). DOI: 10.1126/science.adi4639

Journal information: Science 

© 2023 Science X Network

SpaceX launches Starlink satellites from California

 

Test of police implicit bias training shows modest improvements

by Sara Zaske, Washington State University

Credit: Pixabay/CC0 Public Domain

A two-part training designed to help police officers recognize their implicit bias, revealed some behavior improvement and lowered citizen discrimination complaints in a controlled study. While a small study involving one police department, it is the first-known research to provide evidence that this type of training can produce positive behavioral effects.

Led by Washington State University researcher Lois James, the study found some improvement in the anti-bias trained officers' behavior toward homeless people in particular, compared to a control group. The trained officers also had 50% fewer discrimination complaints overall, though these were low at the start with—21 before and 11 after the training. The researchers detailed their findings in Policing: An International Journal.

While more research needs to be done, the findings are promising, said James.

"We did see these small but significant decreases in disparities in how officers treated different types of people and in community member discrimination complaints for the group that received this combined training intervention," said James. "This provides some preliminary evidence that implicit bias training could be impactful and that we could start to see some positive changes."

For the study, the researchers had 50 Sacramento, California police officers take 12-hours total of coursework and Counter Bias Simulation training, or CBTSim, an interactive training James helped develop which uses full-scale video to create virtual simulations of citizen encounters.

The researchers then assessed bodycam footage from actual patrol shifts to analyze interactions of the officers before and after the training as well as those of a control group. They coded specific officer behaviors, such as whether they offered a polite greeting, explained the purpose of the encounter and tried to de-escalate volatile situations.

The analysis found a small but significant improvment in the officers' interactions overall following training, and a reduction in disparities around how officers interact with people suffering homelessness across different racial and gender groups. They also found community complaints about discrimination of any type were lower for the officers who had undertaken the training.

As opposed to explicit prejudice against people who are different, implicit bias is unconscious. Many scholars believe this type of bias is hard-wired into humans by evolution, stemming from a time when anyone from outside a kin group was a potential threat. Since implicit bias does not serve modern humans well, especially in fields like law enforcement, researchers and educators have been trying to come up with trainings to make people aware of their implicit bias and combat its effect.

Until this study, research has been unable to validate that such trainings are effective. For instance, a large 2020 study of the New York Police Department found that while an anti-bias classroom training raised officers' awareness of implicit bias, it didn't seem to have an effect on outcome measures, including use of force and citizen complaints.

For this study, the Sacramento police officers not only trained in the classroom but also on CBTSim, which allows officers to go through simulated scenarios and then analyze their own responses.

"We're trying to bring implicit bias into the person's conscious awareness because if we're aware of our mental filter, then we have more control—and just the general ability to influence our own behavior," said James.

The effect sizes were small and broader research is needed to confirm the findings, the authors emphasized. However, the findings provide some hope, James said, especially since this was a relatively short training period and longer trainings tailored to each police agency may have greater effects.

"This study provides a tentative positive message: We shouldn't give up on implicit bias training," she said. "It doesn't mean that implicit bias training is going to fix all the problems, but it could help."

More information: Lois James et al, Results from an effectiveness evaluation of anti-bias training on police behavior and public perceptions of discrimination, Policing: An International Journal (2023). DOI: 10.1108/PIJPSM-01-2023-0014

Provided by Washington State University 

Diversity training for police officers: One-and-done efforts aren't enough