Climate Science Loses a Bright Light

Shock spread through the climate science community today with the news that Stanford’s Stephen Schneider has died.

Steve Schneider was a fearless advocate of climate action (Photo: Stanford University)

Schneider reportedly suffered a heart attack on a flight from Stockholm to London. Schneider founded a scientific journal on the subject of climate change and was a vocal advocate of the need for policy action, to respond to the threat posed by global warming.

A release issued by  Stanford today reads, in part:

“Steve, more than anything, whether you agreed with him or not, forced us to confront this real possibility of climate change,” said his colleague at Stanford’s Woods Institute for the Environment, Jeff Koseff.

Schneider was influential in the public debate over climate change and wrote a book, Science as a Contact Sport: Inside the Battle to Save Earth’s Climate, about his experiences. He also wrote a book about his battle with leukemia, Patient from Hell.

He had been a White House consultant in the Nixon, Carter, Reagan, George H.W. Bush, Clinton, George W. Bush and Obama administrations.”

Schneider last appeared on KQED’s air just after the UN climate talks ended in last December, with what many considered a whimper. His disappointment was palpable as he spoke with Forum host Dave Iverson over a tenuous cell phone connection from Copenhagen (Schneider joins the program about 30 minutes in). He also made Forum appearances in programs in 2007 and 2004.

On his widely read Dot Earth blog for the New York Times, Andrew Revkin offers a personal perspective on Schneider, his work, and his bigger-than-life personality.

Humans and Climate, Past and Future

Arctic cottongrass, a tundra plant that may increasingly be replaced by birch as temperatures warm, studies show. (Photo: Gretchen Weber)

Two new studies out of Stanford’s Carnegie Institution for Science raise interesting questions about human influence on the future of the world’s climate and about our role in global warming thousands of years ago.

The first study, authored by Ken Caldeira and Long Cao, used models to examine the climatic effects of actively removing CO2 from the atmosphere.  What they found is that even if all CO2 emissions were magically halted, and CO2 levels in the atmosphere were instantly reduced to pre-industrial levels, the resulting drop in temperatures would offset less that half of the CO2-induced warming.

This discrepancy, the scientists say, is due to complexities in the carbon cycle.  First, as CO2 in the atmosphere drops, the ocean, which acts as a carbon sink by absorbing CO2 from the air, will release more of its stored carbon.  Second, the carbon balance on land will change, too.  As temperature and CO2 concentrations change, soils will begin to release more carbon than plants take in.

Therefore, in order for CO2 scrubbing to be effective, said Caldeira in an email, we may have to commit to it for a long time.  “To maintain atmospheric CO2 at low levels would require removing CO2 from the atmosphere as it degassed from the oceans and land surface. This process takes many decades, even centuries,” he wrote.

That revelation, “has obvious implications for the public and for policy makers as we weigh the costs and benefits of different ways of mitigating climate change,” according to Caldeira.

The second study, which has been the target of some skepticism in the blogosphere, suggests that humans may have been influencing the climate thousands of years ago, long before was previously believed.  In the paper, authors Chris Doughty, Chris Field, and Adam Wolf, all of the Carnegie Institute, propose that the extinction of mammoths 15,000 years ago, caused in part by human hunters, may have contributed to global warming by causing a change in the albedo of the land surface in the far north.  Mammoths ate birch, which kept the dark green plant in check across the grasslands of North America and present-day Russia. As the population of the large mammals declined, the authors assert, the birch spread and dominated the lighter-colored grasslands, which effectively changed the color of the landscape.  A darker land surface absorbs more heat than a light one. This in turn heats up the air, creating a positive feedback loop that encourages the spread of more birch.

The authors estimate that the mammoth extinction could account for approximately one-quarter of the spread of birch at that time, and that the increased birch cover could have warmed the planet .18 degrees F over several centuries.

Paddling the Coast for Climate Clues


Lane Hartman, Ian Montgomery, and Michael Taylor. Photo courtesy of Ian Montgomery.

Three Stanford students are starting a summer trip down the California coast today. They’ll be enjoying the views and the ocean breeze, but not from a convertible cruising down Highway 1. They’re kayaking from Monterey to San Diego. It’s going to take 2 months.

“If we walked we could go faster,” says Ian Montgomery, a sophomore Earth Systems major. He’s making the 400-mile trip with Lane Hartman and Michael Taylor. The three are united by, as they explain on their blog, a “love for surfing and great bodies of water” (Montgomery is from Southern California, Hartman and Taylor are from Michigan and the Marshall Islands, respectively).

Montgomery expects the slow pace (about 10 miles a day) and the sheer novelty of the expedition will provide opportunities to talk to locals about changes they’ve seen along the coast. The students will stop along the way to talk to ecologists, representatives from environmental groups, fishermen, and coast residents.

The students did a test run earlier this week.

Photo: Lane Hartman.

The intertidal zone is an interesting place to study climate change, explains Montgomery, because there are so many variables: air temperature, water temperature, tidal action, and human impacts.

As the students travel they won’t just be collecting anecdotal evidence. They’ll take note of what animals they see in the water and also take pictures of the intertidal zone as they go along. By photographing a 25 centimeter by 25 centimeter square a day, they’ll create a series of snapshots of what lives where on the California coast.

They’ll be able to compare their findings with research from last century done by  marine biologist–and friend of John Steinbeck’s–Ed Ricketts. Montgomery unearthed Ricketts’s records of what species lived in the intertidal zone in Monterey in the ’20s and ’30s (some of the records are singed on the edges, survivors of a fire that tore through Ricketts’s lab in the 1930s). Montgomery suspects they’ll find that species have moved since then, pressed north by warmer temperatures. He already knows some have, like the tube snail (serpulorbis squamigerus), a species that was once limited to Southern California, but is now common in Monterey Bay.

You can follow their progress and see pictures from the trip on the students’ blog.

NASA Launches Arctic Sea Ice Expedition

Coast Guard Cutter Healy (Photo by Petty Officer Patrick Kelley, US Coast Guard)

Coast Guard Cutter Healy. Photo: Petty Officer Patrick Kelley, US Coast Guard

Next week, a NASA team of more than 40 scientists will take to the seas for a five-week expedition in the Arctic to study how changing conditions there are affecting ocean chemistry and ecosystems.  The voyage, NASA’s first dedicated oceanographic research mission, is named ICESCAPE, which stands for “Impacts of Climate on Ecosystems and Chemistry of the Arctic Pacific Environment.”  It will take place aboard the US Coast Guard Cutter Healy.

“We’re  trying to address what is the long term impact of climate variability and change, both natural and anthropogenic, on the biogeochemistry and ecology of the Arctic,” said Paula Bontempi, program manager for NASA’s ocean biology and biogeochemistry research program.

The expedition will give scientists a chance to make field observations about the ocean, sea ice, and the atmosphere in regions where researchers often must rely on remote sensing technology for their data.  One main focus of the research will be to observe how changes, such as a substantial decrease in sea ice, may be affecting the ocean’s ability to absorb CO2 from the atmosphere and the consequent effects on ecosystems.

“The Arctic is in the midst of some substantial changes,” said ICESCAPE Chief Scientist Kevin Arrigo of Stanford.  “In the last 10 years, the ice-free season in the Arctic Ocean has increased by about 45 days.  And this has a big impact on organisms in the Arctic that are keyed to these events.”

Arrigo says that the sea ice retreats about 28 days sooner than it did just a decade ago, and advances about 17 days later. He says this change has shifted the timing of food production.  Phytoplankton, the base of the food chain in the Arctic Ocean, are now growing a month earlier than they did in the 1990s, says Arrigo, which could spell a problem for organisms such as the California gray whales, which time their migrations around peak food production.

“Over the years satellite imagery has shown a significant decline in the Arctic ice cover,” said Don Perovich, a research geophysicist at the Cold Regions Research and Engineering Laboratory in Hanover, NH, who is part of the ICESCAPE expedition. “But there’s really more to it than just the ice.  It’s important to remember that sea ice isn’t just some isolated component. It’s part of larger system.”

Sea ice, he said, serves as a barrier between the atmosphere and the ocean, limiting the exchange of heat, moisture and gases; acts as a reflector of sunlight; and is a habitat for a rich marine ecosystem.

“It’s an ecosystem where sea ice and biology are intricately intertwined,” said Perovich. “You can think of the ice and the biology as executing this intricate dance, but it’s a dance where one of the partners has started changing its steps. And that partner is the sea ice cover.”

The 2010 ICESCAPE expedition starts in Dutch Harbor in the Aleutian Islands, will continue across the southern Chukchi Sea and into the Beaufort Sea along Alaska’s northern shelf.  A second expedition is planned for 2011.   NASA estimates the cost of the ICESCAPE project to be $10 million over four years.

The expedition blog has already launched, and will be updated daily once the expedition is underway, according to NASA spokesman Steve Cole.

I’ll be launching my own “Arctic expedition” next week.  Starting June 18th, I’ll be spending two weeks with climate scientists at the Toolik Field Station in northern Alaska, as part of the Logan Science Journalism Program, run by the Marine Biological Laboratory in Woods Hole, MA.   Check back here for periodic dispatches about the science, the landscape, and the impacts of constant daylight on one journalist’s mental state.

Campus as Climate Microcosm

Felt Reservoir, Stanford University  (photo: Gretchen Weber)

Felt Reservoir, Stanford University. Photo: Gretchen Weber

On a recent weekend, a couple of dozen hearty souls hiked more than 20 miles across the sprawling lands of Stanford University, to learn about global warming and see first-hand how the changing climate is affecting the campus.  It was the fourth annual “Walk the Farm” outing, a trek organized by the Bill Lane Center for the American West and led by its Executive Director, Jon Christensen.  Each year, the hike takes a different route through Stanford’s more than 8,000 acres, and is designed to use the university as a microcosm for a different global theme.  This year’s was climate change.

Throughout the 12-hour day, Stanford researchers joined the hikers to talk about the effects of climate change on the campus and region, as well as the related research taking place at the university.   Biology professor Carol Boggs spoke about her research on the Bay checkerspot butterfly, its extirpation in the region, and plans for a possible future reintroduction of the species on campus.  Other presenters included climate scientists Chris Field and Steven Schneider, and biologist Scott Loarie.

Watch this six-minute video for an overview of this year’s Walk the Farm hike and highlights from some of the talks along the way:

Hear more from Carol Boggs about the Bay checkerspot butterfly:

Scott Loarie explains how a rapidly changing climate is posing challenges for species migration in the video below:

The Air Quality-Carbon Connection

I-80Here’s a news flash: California has an air pollution problem.  According to the American Lung Association’s 2009 State of the Air Report, 38 of California’s 52 counties get failing grades for either high ozone or particle pollution days.  (You can see your own county’s grades for ozone and air particle pollution at the State of the Air website.)

In fact, last month the federal EPA’s new director for San Francisco-based Region 9 made an astonishing claim on KQED’s Forum program. Jared Blumenfeld said that more Californians die from air pollution than from car wrecks. When a caller asked him to back up the claim, Blumenfeld provided the following statistics:

– Traffic-related fatalities: 3,949 deaths per year from 3,535 fatal collisions (average for 1999-2008)
– Deaths associated with PM2.5 exposure above 5 ug/m3 in California : 18,000 deaths per year

Cars are doing double duty in these statistics, since passenger vehicles are a large source of air pollution. Over the decades the state has addressed this fact with landmark efforts to regulate vehicle emissions, in efforts initially to improve local air quality and more recently, to reduce greenhouse gas emissions.

In a new study released this week by the Public Policy Institute of California (PPIC),  researchers looked at two state priorities: reducing greenhouse gas emissions that cause global warming and improving air quality to benefit public health, and evaluated the effectiveness of four potential transportation strategies to address both.

What they found is something that policymakers have known all along: there are no easy answers.  And everything involves a trade-off.

PPIC research fellow Louise Bedworth compared the cost, public health benefits, and GHG reduction potential for various alternative-fuel vehicles; battery-electrics, fuel cell, ethanol, and for reducing overall vehicle miles.  What she found is that transforming California’s vehicle fleet to battery-electric vehicles provides the greatest public health benefit, but that high costs and technological uncertainty make this option far from ideal.

On the flip side, said Bedsworth, while we have the technology for vehicles to run on corn-based ethanol, research shows that when indirect land-use costs are considered, corn-based biofuels provide no significant public health or climate change benefit.

But while the PPIC looks at local health and global warming effects separately, a new study out of Stanford has found that the two are directly linked. It’s well established that carbon dioxide contributes to global warming and that increased temperatures can exacerbate air pollution, but the new study shows that CO2 “domes” that develop over urban areas are, in fact, causing health problems for city-dwellers.  The study, conducted by civil and environmental engineering professor Mark Jacobsen, looked at models for the contiguous 48 states, for California and for the Los Angeles area. Results showed an increased death rate in all three areas compared to what the rate would be if no local carbon dioxide were being emitted.

Neither current regulations, nor the federal cap-and-trade bill passed by the House address the local effects of CO2 emissions on health.  Jacobsen says that this study provides evidence that they should.  He estimated an increase in premature mortality of 50-to-100 deaths per year from local CO2 emissions in California.

Jacobsen talks about his study in the video, below.

Chu: Time to End “Paralysis”

Gretchen Weber

Photo: Gretchen Weber

Energy Secretary Steven Chu returned to his old stomping grounds at Stanford University yesterday with a broad outline for jump-starting “a clean energy industrial revolution.”  Speaking to a packed auditorium of students and faculty, Chu advocated the passage of a comprehensive energy bill, saying that increased innovation and investment in “clean tech” is essential for American competitiveness, as well as for reducing dependence on foreign oil and mitigating climate change:

“We are right now in a state of paralysis. There are many businesses who say ‘No, no, we can’t do this, this country was founded on cheap energy, that’s what I want.’  That’s just holding off the inevitable.  So if we hold off the inevitable for another 5 or 10 years, I think we will lose.  Because the other countries are moving.  And then we play catch up.  And then we import their stuff.  That’s what’s at risk.  The future of the prosperity of the US is at risk.  Energy touches everything.”

Chu said the United States is “not doing so well” in terms of clean energy innovation and cited the drop in US market share in photovoltaics  from 44% in 1996 to less than 10% today.

“The US innovation machine is the best in the world,” he said, and then recited a dismal laundry list of fields in which the US is no longer leading the way, including auto fuel efficiency, hybrid car batteries, energy transmission, energy transmission equipment, and nuclear technology.

When asked by an audience member why the US doesn’t commit to a Manhattan Project-style endeavor to solve the energy issue, Chu explained that a project at that scale would have an annual cost in the tens of billions.  In comparison, the current base budget of the DOE is $3 billion per year.

“I agree.  We should do that,” he said. “Tell people in Congress how important it is.”

Key to America’s success, he said is an energy bill that sends signals to the private sector that clean energy is a profitable venture, through incentives and tax breaks.  He said that the federal government plays a role in grants and loan guarantees, but to scale technologies from the idea stage to the factory floor, private investors must play a role.

“America has an opportunity to seize the day and to lead in what has to be a new industrial revolution,” said Chu.  “It’s our choice. Do we want to be leaders or followers?”

As if on cue, it looks like Los Angeles is about to crush one plan that might have helped put southern California at the forefront of clean energy generation and transmission. The Riverside Press-Enterprise reports today that Los Angeles officials will likely announce tomorrow that they’re pulling the plug on the contentious project known as Green Path North.   The project would have installed 80 miles of high-voltage lines and towers to carry geothermal, wind and solar energy from Imperial County to Los Angeles and some Inland cities.  The plans have met with opposition from environmental groups and communities along the proposed corridors.

The project was featured last year in a radio series for Climate Watch by KQED’s Rob Schmitz, on plans to get clean energy from southern California’s deserts to its cities.

New Plan: 100% Renewables by 2030

30521491Wind, water and solar energy can provide more than enough energy to power the world, according to a new plan proposed by two California scientists in the November issue of Scientific American.

Stanford civil and environmental engineering professor Mark Z. Jacobson and UC Davis researcher Mark Delucchi crunched the numbers and have concluded that if the world used existing technology to convert entirely to electricity (and hydrogen powered by these renewables) by 2030, the world’s power demand would be reduced by 30%, from the expected 16.9 terawatts to 11.5 terawatts.  They base this expected reduction on the premise that fossil fuel and biomass combustion are inefficient, losing up to 80% of the produced energy to heat. With energy produced by electricity, only 20% is lost as heat.

Even without this reduction in world energy needs, the two researchers assert that there is more than enough renewable energy available to meet the world’s needs (their data pegs the potential worldwide energy from wind at 1,700 TW and solar at 6,500 TW).  When difficult-to-reach areas and protected lands are excluded from their calculations, the scientists find at least 40 TW available from wind and 580 from solar.   Currently, they find, we generate only .02 TW of wind and .008 of solar.

The ambitious plan calls for 3.8 million large wind turbines, which, when spaced appropriately would occupy 1% of the Earth’s land, and 89,000 300-megawatt photovoltaic and concentrated solar power plants, which would occupy .33% of the Earth’s land surface.  The plan also requires 490,000 tidal turbines; 5,350 geothermal plants; 720,000 wave converters; and 1.7 billion rooftop photovoltaic systems.  Less than 2% of these energy producing installations current exist.  The plan also requires 900 hydroelectric plants, of which 70% are currently operational.

“I know it’s possible,” said Jacobson. It’s just a question of whether people want to do it.”

Of course, overhauling the entire world energy economy in 20 years is a Herculean task to say the least, and the researchers are upfront about the obstacles their plan faces.   They concede that not only would there need to be significant political support in the form of feed-in-tariff (FIT) programs, taxes on fossil fuels, and significant investment in long-distance transmission systems, but materials availability could also be a barrier in the long term.

“It’s all a question of politcal will,” said Jacobson. “It’s not a technical problem. If we shifted subsidies to things that are clean, that’s being smart. Why invest in something that puts out more carbon and air pollution rather than something that doesn’t?”

The idea of shutting off all of the world’s coal and nuclear plants and building hundreds of miles of wind farms and solar arrays  is controversial to say the least.  Aside from (not exactly minor) political, social, and economic obstacles, there is the issue of baseload power–what’s available around the clock, rain or shine, to keep the lights on–which we currently draw primarily from nuclear and fossil fuel plants.   Proponents of nuclear power like Stewart Brand argue that until there’s a massive storage system for wind and solar energy, renewables will remain supplemental sources of energy.

Jacobson and Delucchi do address this issue in their article. “Intermittency problems can be mitigated,” they write, “by a smart balance of sources, such as generating a base supply from steady geothermal or tidal power, relying on wind at night when it is often plentiful, using solar by day and turning to a reliable source such as hydroelectric that can be turned on and off quickly to smooth out supply or meet peak demand.”

Stanford Studies Clean Coal Tech for China

coal_blogChina, the world’s largest emitter of CO2, is the focus of a new $2 million investment in clean coal technology research by  Stanford’s Global Climate and Energy Project (GCEP).

The project will fund research into large-scale carbon sequestration in underground geological formations. China relies heavily on coal for electricity generation and in 2006 was reported to be building the equivalent of one new coal-fired power plant every week.

“China is growing so rapidly, and if they’re going to be able to lower their emissions, they are going to need a whole suite of technologies,” said Sally Benson, director of GCEP.  “They are doing a lot with solar technologies and energy efficiency but China is not abandoning coal.  So, we’re looking for ways they can reduce their emissions from coal.”

The three-year project is an international collaboration among the University of Southern California (USC), Peking University (PKU) and China University of Geosciences at Wuhan (CUG). It will focus on the technical aspects of stashing carbon in saline aquifers, such as chemical reactions between the rock and carbon and understanding what portions of the aquifers can actually be filled up.  The research will involve 39 scientists and students, and will integrate geological modeling, reservoir simulation and laboratory experiments.   The results may shed needed light on China’s overall carbon storage potential.

“Saline aquifers have been shown to have the biggest storage capacity across the world,” said Benson, “and China has a tremendous need.”

China’s not the only country with a tremendous need.  As the second largest emitter of CO2 (and still bigger than China per capita), the United States has yet to deploy large-scale CCS. Yesterday, the U.S. Department of Energy announced $27.6 million in new funding for 19 projects exploring potential carbon storage technologies.

Heat Relief for Coral Reefs?

This post is condensed from a Stanford News Service release. Cassandra Brooks is a science-writing intern at the Woods Institute for the Environment at Stanford.

Reed Galin

Photo: Reed Galin

Stanford scientists find heat-tolerant coral reefs that may resist climate change

By Cassandra Brooks

Some experts say that more than half of the world’s coral reefs could disappear in the next 50 years, in large part because of higher ocean temperatures caused by climate change. But now Stanford University scientists have found evidence that some coral reefs are adapting and may actually survive global warming.

“Corals are certainly threatened by environmental change, but this research has really sparked the notion that corals may be tougher than we thought,” said Stephen Palumbi, a professor of biology and a senior fellow at Stanford’s Woods Institute for the Environment.

Palumbi and his team began studying the resiliency of coral reefs in the Pacific Ocean in 2006. “The most exciting thing was discovering live, healthy corals on reefs already as hot as the ocean is likely to get 100 years from now,” said Palumbi, director of Stanford’s Hopkins Marine Station. “How do they do that?”

Coral reefs form the basis for thriving, healthy ecosystems throughout the tropics. They provide homes and nourishment for thousands of species, including schools of fish that feed millions of people across the globe.

Corals rely on partnerships with tiny, single-celled algae called zooxanthellae. The corals provide the algae a home, and, in turn, the algae provide nourishment, forming a symbiotic relationship. But when rising temperatures stress the algae, they stop producing food, and the corals spit them out. Without their algae symbionts, the reefs die and turn stark white, an event referred to as “coral bleaching.”

During particularly warm years, bleaching has accounted for the deaths of large numbers of corals. In the Caribbean in 2005, a heat surge caused more than 50 percent of corals to bleach, and many still have not recovered, according to the Global Coral Reef Monitoring Network, an international collaboration of government officials, policymakers and marine scientists, including Palumbi.

Havens of healthy reefs

In recent years, scientists discovered that some corals resist bleaching by hosting types of algae that can handle the heat, while others swap out the heat-stressed algae for tougher, heat-resistant strains. Palumbi’s team set out to investigate how widely dispersed these heat-tolerant coral reefs are across the globe and to learn more about the biological processes that allow them to adapt to higher temperatures.

In 2006, Palumbi and graduate student Tom Oliver, now a postdoctoral researcher at Stanford, traveled to Ofu Island in American Samoa. Ofu, a tropical coral reef marine reserve, has remained healthy despite gradually warming waters.

The island offered the perfect laboratory setting, Oliver said, with numerous corals hosting the most common heat-sensitive and heat-resistant algae symbionts. Ofu also has pools of varying temperatures that allowed the research team to test under what conditions the symbionts formed associations with corals.

In cooler lagoons, Oliver found only a handful of corals that host heat-resistant algae exclusively. But in hotter pools, he observed a direct increase in the proportion of heat-resistant symbionts, suggesting that some corals had swapped out the heat-sensitive algae for more robust types. These results, combined with regional data from other sites in the tropical Pacific, were published in the journal Marine Ecology Progress Series in March 2009.

Global pattern

To see if this pattern exists on a global scale, the researchers turned to Kevin Arrigo, an associate professor of environmental Earth system science at Stanford and an expert on remote satellite sensing of marine microalgae. Arrigo gathered worldwide oceanographic data on a variety of environmental variables, including ocean acidity, the frequency of weather events and sea-surface temperature.

Oliver then compiled dozens of coral reef studies from across the tropics and compared them to Arrigo’s environmental data. The results revealed the same pattern: In regions where annual maximum ocean temperatures were above 84 to 88 degrees Fahrenheit (29 to 31 degrees Celsius), corals were avoiding bleaching by hosting higher proportions of the heat-resistant symbionts.

Most corals bleach when temperatures rise 1.8 F (1 C) above the long-term normal highs. But heat-tolerant symbionts might allow a reef to handle temperatures up to 2.6 F (1.5 C) beyond the bleaching threshold. That might be enough to help get them through the end of the century, Oliver said, depending on the severity of global warming.

A 2007 report by the United Nations International Panel on Climate Change concluded that the average surface temperature of the Earth is likely to increase 3.6 to 8.1 F (2 to 4.5 C) by 2100. In this scenario, the symbiont switch alone may not be enough to help corals survive through the end of the century. But with the help of other adaptive mechanisms, including natural selection for heat-tolerant corals, there is still hope, Oliver said.

Heat-resistant corals also turn out to be more tolerant of increases in ocean acidity, which occurs when the ocean absorbs excess carbon dioxide from the atmosphere–another potential threat to coral reefs. This finding suggests that corals worldwide are adapting to increases in acidity as well as heat, Oliver said, and that across the tropics, corals with the ability to switch symbionts will do so to survive.

“Although we are doing things to the planet we have never done before, it’s hard to imagine that these corals, which have existed for a quarter of a billion years, only have 50 years left,” Palumbi said. “And part of our job might be to figure out where the tougher ones live and protect those places.”

For more on this story: