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Sha'Carri Richardson looks on after winning the women's 100 meter final at the U.S. Olympic Track & Field Team Trials on June 19, 2021 in Eugene, Oregon. Image Credit: Patrick Smith, Getty Images

Cannabis doesn’t enhance performance. So why is it banned in elite sports?

At the 1998 Winter Olympics in Nagano, Japan, snowboarding made its debut as an Olympic sport. No longer relegated to the fringes, snowboarders took to the snow-capped peaks of Mount Yakebitai, and 26-year-old Canadian Ross Rebagliati rose to global fame. But shortly after he won gold in the giant slalom event, a drug test revealed <a href="https://deadspin.com/how-a-stoned-canadian-changed-sports-history-990167249">17.8 nanograms</a> per milliliter of THC, the psychoactive compound in cannabis, in Rebagliati’s system, which he still attributes to <a href="https://www.usatoday.com/story/sports/olympics/2013/07/17/ross-rebagliati-olympics-marijuana-drug-testing/2528283/">secondhand smoke</a>.“Cannabis back then was seen as being for losers and lazy stoners,” Rebagliati told <a href="https://www.nytimes.com/2018/11/02/world/canada/canada-pot-snowboarder-olympics.html">The New York Times.</a> “The big corporate sponsors didn’t want to sponsor me. I became a source of entertainment, a joke. I went from hero to zero overnight.”Rebagliati was initially stripped of his medal, but because cannabis had not been <a href="https://www.washingtonpost.com/wp-srv/sports/longterm/olympics1998/sport/snowboard/articles/medal12.htm">officially banned</a> by the International Olympic Committee (IOC), he was ultimately able to keep the gold. Two months after his failed drug test, the <a href="https://www.deseret.com/1998/4/27/19376774/ioc-adds-marijuana-to-its-no-no-list">IOC officially banned cannabis</a> due to its illicit status as a social drug.
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<h3>The politicization of pot </h3>As the war on drugs was waged on America’s streets, it was also playing out in sports arenas around the world. “We had to draw a lesson from Nagano,” IOC Director General Francois Carrard told the <a href="https://www.deseret.com/1998/4/27/19376774/ioc-adds-marijuana-to-its-no-no-list">Associated Press</a> in 1998. “The IOC wants to take a stand against a social drug."Prince Alexandre de Merode, chairman of the IOC medical commission at the time, added that cannabis should be banned even though it <a href="https://www.deseret.com/1998/4/27/19376774/ioc-adds-marijuana-to-its-no-no-list">does not act as a performance-enhancer</a> like steroids.Roger Pielke Jr., an expert in sports governance and a professor of environmental studies at the University of Colorado Boulder, claims that “the deeper reality was that the Clinton administration’s focus on anti-doping regulations helped serve its domestic policy agenda, which was focused on waging a war on drugs.”In 1998, the United States <a href="https://www.washingtonpost.com/sports/olympics/2021/07/03/shacarri-richardson-marijuana-olympics-doping-ban/">pledged an unprecedented $1 million</a> to assist the IOC in its mission to eradicate drugs from elite sports. Barry McCaffrey, director of the Office of National Drug Control Policy, was adamant that recreational drugs such as cannabis should be just as much of a priority for the international sports community as performance-enhancing drugs. “We raise Olympic athletes up on international pedestals for all the world’s children to look up to as role models—it is vital that the message they send is drug-free,” McCaffrey wrote in a <a href="https://apnews.com/article/36e9c87e8521c6553ef208d390b2885c">10-page memo to the IOC</a>. “The goal of this whole effort must be to prevent Olympic medals and the Olympic movement from being tarnished by drugs.”
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<img alt="Snowboarder passing slalom flag" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/RossRebagliati.width-990_zqFeMju.jpg"/>
<figcaption>Snowboarder Ross Rebagliati at the 1998 Winter Olympics in Nagano, Japan, where he won gold for Canada in the men's giant slalom. Image Credit: Mark Sandten, Bongarts, Getty Images
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According to Pielke, <a href="https://www.govinfo.gov/content/pkg/CHRG-106shrg75594/pdf/CHRG-106shrg75594.pdf">Rebagliati’s case</a> gave the U.S. government the leverage it needed to lobby U.S. anti-doping leaders to include marijuana on the <a href="https://www.wada-ama.org/en/what-we-do/the-prohibited-list">World Anti-Doping Agency’s (WADA) Prohibited List</a>.<a href="https://bit.ly/3BZs1hY">WADA was established in 1999</a> through a collective initiative led by the IOC, and maintains the <a href="https://www.usada.org/about/world-anti-doping-code/">World Anti-Doping Code</a> and prohibited list. Its key role is to standardize anti-doping regulations globally for Olympic sports. Director McCaffrey led the U.S. delegation at the first official meeting of WADA, after which “WADA looked far more like the institution the United States and its other international partners called for, than the original IOC-formed WADA” according to <a href="https://www.ojp.gov/pdffiles1/Digitization/185694NCJRS.pdf">a report</a> from the White House Office of National Drug Control Policy (ONDCP) on the agency’s actions and accomplishments from 1993-2000. The United States is also the largest <a href="https://www.reuters.com/article/us-sport-doping/u-s-threatens-to-pull-wada-funding-as-war-of-words-escalates-idUSKBN23V2TO">individual contributor</a> to WADA, which receives half of its funding from the IOC, and half from governments around the world. In 2020, the U.S. pledged over $2.7 million of the $37.4 million WADA budget. Despite the U.S. government’s stance on social drugs, the ONDCP acknowledged that the athletic community itself was less concerned about cannabis than about performance-enhancing substances, like anabolic steroids, which can promote <a href="https://www.scientificamerican.com/article/a-rod-steroids-better-athlete/">tissue growth and muscle generation</a> and shorten recovery time after a workout.  “In the course of our efforts to put in place an IOC ban on marijuana, athletes and sports officials at all levels—ranging from Olympians to high school coaches to youth athletes—informed ONDCP that they felt that the more urgent drug threat within the sports world was the use of performance enhancing drugs,” the <a href="https://www.ojp.gov/pdffiles1/Digitization/185694NCJRS.pdf">ONDCP report</a> stated. These concerns, the report notes, were “scientifically grounded” by the results of the 1999 <a href="https://www.drugabuse.gov/drug-topics/trends-statistics/monitoring-future">Monitoring the Future</a> survey, which concluded that youth steroid use increased roughly 50% over the prior year’s study. 
<h3>Why is cannabis banned? </h3>According to WADA, any substance may be included on its prohibited list if it meets <a href="https://www.wada-ama.org/en/questions-answers/prohibited-list-qa#item-391">two of three criteria</a>: it has the potential to be performance enhancing, it poses a potential or actual health risk to the athlete, or it violates the “spirit of the sport.”WADA did not respond to questions from NOVA about the prohibited list or cannabis’s status on the list. But several recent studies investigate whether cannabis has performance-enhancing qualities in athletic competition. A <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7819470/">2020 literature review</a> by researchers not associated with WADA concluded, “there appears to be no reason based on current data to believe that cannabis has any significant ergogenic [performance-enhancing] effect.” An independent <a href="https://pubmed.ncbi.nlm.nih.gov/32734752/">2021 review</a> echoed that conclusion, saying cannabis “does not act as a sport performance enhancing agent as raised by popular beliefs.”“In no circumstances is (cannabis) ever a performance enhancing substance. It is a net negative in terms of athletic ability and performance,” says Jeff Anderson, a professor of radiology and imaging sciences at the University of Utah who studies how the brain responds to compounds found in cannabis. “On the whole, people under the influence of THC are not able to perform as well on cognitive tests, they have slowed reaction times, decreased executive function, decreased attention.”
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Two decades after WADA banned cannabis, U.S. track and field sprinter Sha’Carri Richardson delivered a show-stopping performance <a href="https://www.youtube.com/watch?v=W5jWmeCZzp4">at the Olympic trials</a>, followed by an emotional interview in which she said she learned the week before that her birth mother had died. However, Richardson’s dreams of competing at the (delayed) 2020 Summer Olympics in Tokyo were dashed when she tested positive for THC, renewing a discussion about <a href="https://www.nytimes.com/2021/07/09/sports/olympics/marijuana-sports-performance-enhancing.html">cannabis’s impact on performance</a>.Since cannabis was banned, the public perception and legal landscape surrounding its use have changed greatly. While cannabis is illegal at a federal level, medical cannabis is legal in <a href="https://www.businessinsider.com/legal-marijuana-states-2018-1">37 states</a>, and cannabidiol (CBD)—reportedly used by <a href="https://www.upi.com/Top_News/US/2019/08/08/Poll-1-in-7-Americans-use-CBD-products-mostly-young-adults/9481565274864/">1 in 7 Americans</a>—is no longer prohibited by WADA. In the court of public opinion, where Rebagliati once found infamy, <a href="https://www.nbcnews.com/news/us-news/advocates-say-thc-does-not-enhance-sports-performance-so-why-n1272979">Richardson found support</a>, and her case left many <a href="https://www.scientificamerican.com/article/weed-shouldnt-be-banned-for-elite-athletes-some-experts-say/">questioning the science</a> behind cannabis’s prohibited status.  “Drug testing is yet another tool of the drug war, and it’s a failure,” Kassandra Frederique, executive director of the Drug Policy Alliance, said <a href="https://drugpolicy.org/press-release/2021/07/drug-policy-alliance-statement-shacarri-unjust-suspension-us-olympics-team">in a statement</a>. “Sha’Carri’s suspension serves as a cautionary tale and a reminder of how insidious the drug war is in our everyday lives, far beyond the carceral state.” 
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<img alt="Cannabis plants at Glass House Farms" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/Cannabis-STILL2.width-990_8DCrnB4.png"/>
<figcaption>The cannabis plant contains over 400 chemicals, including the cannabinoids tetrahydrocannabinol (THC), the primary psychoactive compound, and cannabidiol (CBD). Image Credit: NOVA/GBH
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<h3>Cannabis in the body</h3>Under the <a href="https://www.wada-ama.org/en/questions-answers/prohibited-list-qa#item-391">guidelines outlined by WADA</a>, “all natural and synthetic cannabinoids that mimic the effects of THC are prohibited, however CBD is not prohibited.”A cannabinoid is a compound that—no matter the source—interacts with cannabinoid receptors, which are found in <a href="https://www.pbs.org/wgbh/nova/video/endocannabinoid-system/">nearly every organ in the human body</a>. THC, for example, affects cannabis users by binding to cannabinoid receptors in and outside the brain, causing cells to behave differently. (The receptors also bind with the body’s natural cannabis-like chemicals, called <a href="https://www.pbs.org/wgbh/nova/video/endocannabinoid-system/">endocannabinoids</a>.) Since the 1998 Winter Olympics, the THC metabolite limit for Olympic athletes has been raised from <a href="https://www.wada-ama.org/sites/default/files/resources/files/2020-01-11_guidance_note_on_substances_of_abuse_en_0.pdf">15 nanograms per milliliter to 180</a>, purportedly to only detect in-competition use of cannabis. However, the length of time cannabis will stay in a person’s system depends on frequency of use and the amount consumed.This has to do with the way cannabis is metabolized. When smoked, ingested, or otherwise consumed, cannabinoids are absorbed and retained in many parts of the body, <a href="https://www.mayoclinicproceedings.org/article/S0025-6196(16)30825-4/fulltext">particularly fatty tissue</a>. Eventually, the THC byproducts are released and excreted through urine. However, daily consumers of cannabis accumulate THC faster than it can be removed from the body, reports Lia Tabackman for <a href="https://www.insider.com/how-long-does-weed-stay-in-your-system">Insider Health</a>.“Urine testing is one of the most common <a href="https://www.insider.com/how-long-does-weed-stay-in-your-system">drug testing methods</a>,” notes Tabackman. It is also widely used in elite sports. According to a <a href="https://www.mayoclinicproceedings.org/article/S0025-6196(11)61120-8/fulltext">2008 report</a> on drug screening in the journal Mayo Clinic Proceedings, cannabis can be detected in urine for up to three days after a single use. For moderate users (4 times per week), cannabis can still be detected 5 to 7 days after last use. And in heavy daily smokers, it can be detected in urine for up to 30 days or more after they stop.But when it comes to quantifying behavioral impairment while using cannabis, a <a href="https://www.ojp.gov/pdffiles1/nij/grants/255884.pdf">National Institute of Justice study</a> led by researchers from RTI International found that measuring THC levels in blood, urine, and oral fluid were not reliable indicators of marijuana intoxication, regardless of how the cannabis was consumed.“Drug testing does nothing to show current impairment,” Frederique said <a href="https://drugpolicy.org/press-release/2021/07/drug-policy-alliance-statement-shacarri-unjust-suspension-us-olympics-team">in a statement</a>.  The [United States Anti-Doping Agency] must undo this archaic, inhumane, and unscientific policy.”
<h3>"An actual or potential health risk" </h3>In addition to prohibiting it, WADA considers THC <a href="https://www.wada-ama.org/sites/default/files/resources/files/2020-01-11_guidance_note_on_substances_of_abuse_en_0.pdf">a substance of abuse</a>, meaning it is “frequently abused in society outside the context of sport.” Cocaine, heroin, and MDMA (ecstasy) are also on this list. Some mental health experts have expressed concern over the development of <a href="https://pubmed.ncbi.nlm.nih.gov/26502112/">cannabis use disorders</a>, which may lead to increased anxiety or depressive disorders.“I'm among the group that wishes to see cannabis remain on the prohibited list,” says David McDuff, an addiction, trauma, and sports psychiatrist who has served on the IOC's Consensus Panel on Mental Health in Elite Athletes.When McDuff was working at University of Maryland College Park, he says he was shocked by the level of mental health symptoms and disorders within the college athlete population, and that the number of athletes using cannabis on a regular basis jumped across a number of sports.“I was referred to the substance misuse cases and many of them had comorbid anxiety or depressive disorders along with their cannabis use disorder,” says McDuff. “As a clinician, I can't help but tie its use to reduced performance academically and athletically.”Other experts say that while the risk of cannabis abuse is real, it is unfair to not apply the same standards to alcohol, which was no longer prohibited <a href="https://www.wada-ama.org/en/questions-answers/prohibited-list-qa#:~:text=Effective%201%20January%202018%2C%20and,excluded%20from%20the%20Prohibited%20List.">as of 2018</a>.“Alcohol is something that’s far riskier than cannabis use for health, in terms of morbidity and mortality,” Angela Bryan, a professor of psychology and neuroscience at the University of Colorado Boulder, told <a href="https://www.scientificamerican.com/article/weed-shouldnt-be-banned-for-elite-athletes-some-experts-say/">Scientific American</a>. “I think [cannabis] should be treated like other drugs that people use for various reasons—alcohol, caffeine, nicotine. It should be regulated, but I don’t think it should be banned.”McDuff points out that if cannabis is considered a substance of abuse, alcohol should be as well. “Alcohol use would surely violate all three of WADA's criteria.”In September, WADA announced that it is <a href="https://www.wada-ama.org/en/media/news/2021-09/wada-executive-committee-endorses-recommendations-of-non-compliance-of-eight-anti">reviewing cannabis’s status</a> as a prohibited substance, but that it will remain prohibited in competition through 2022. The announcement followed a summer of <a href="https://sports.yahoo.com/wada-reviewing-cannabis-status-as-banned-substance-in-wake-of-sha-carri-richardson-ban-022541468.html">negative media attention</a> and criticism following Richardson’s suspension.In response to <a href="https://twitter.com/RepAOC/status/1411121868795518977?s=20">a request from lawmakers</a> to revisit its policies on cannabis, WADA <a href="https://www.wada-ama.org/sites/default/files/2021_07_letter_from_wada_president_to_jraskin_aocasio-cortez.pdf">pointed out</a> that historically, the U.S. has been “one of the most vocal and strong advocates for including cannabinoids on the Prohibited List.”“WADA has, for more than two decades, faithfully and obediently followed U.S. demands to assist in supporting its domestic drug policy agenda,” says Pielke, “only now to find itself subject to criticism from U.S. policymakers.” 
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Here’s how cannabis use became prohibited—and the science of its biological, psychological, and social effects.

A house on stilts in Nags Head, North Carolina surrounded by high tide surf. Image Credit: John Greim/LightRocket via Getty Images

A major Atlantic current is at a critical transition point

Around 15,000 years ago, the Earth began to transition from a state of heavy glacial coverage to a period of warming. As temperatures rose, large ice sheets that once blanketed much of North America and Europe thawed, and the oceans began to rise.But after 2,000 years of warming, the Earth abruptly cooled to near-glacial conditions. And it stayed that way for more than a thousand years.Scientists have long debated how this abrupt climatic event, which they call the <a href="https://www.ncei.noaa.gov/sites/default/files/2021-11/3%20The%20Younger%20Dryas%20-FINAL%20NOV%20%281%29.pdf">Younger Dryas</a>, occurred. This question has become an urgent one as some researchers think an abrupt climatic event could happen again and disrupt the Gulf Stream, the forceful ocean current that transports warm water from the Gulf of Mexico up North America’s Northeast coast.
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An <a href="https://static1.squarespace.com/static/614dece04ec1fe659b8317d5/t/616354b99fa33305c8a8e81b/1633899707925/Observation-based.pdf">analysis</a> published in the journal Nature Climate Change in August found that the larger system that the Gulf Stream is part of, called the Atlantic Meridional Overturning Circulation (AMOC), is approaching a tipping point. Over the last century, this ocean circulation system has “moved closer to a critical threshold, where it may abruptly shift from the current, strong circulation mode to a much weaker one,” says study author Niklas Boers, a climate researcher at the Potsdam Institute for Climate Impact Research in Germany. Should the AMOC weaken substantially, it could bring intense cold and stronger storms to Europe, raise sea levels across the northeast coast of North America, and disrupt the flow of <a href="https://earthobservatory.nasa.gov/global-maps/MYD28M/MY1DMM_CHLORA">vital nutrients</a> that phytoplankton, marine algae that make up the foundation of the aquatic food web, need to grow in the North Atlantic."It’s important to acknowledge just how big of a system we are trying to measure,” says Nicholas Foukal, a physical oceanographer at Woods Hole Oceanographic Institute who was not involved in the study. “If you calculate the flow of all of the rivers in the world, the amount of water is only about 1% to 2% of the Gulf Stream.”The AMOC is an Atlantic section of a global conveyor belt that drives surface and deepwater currents in every ocean, and influences the rate of sea ice formation at the poles. The AMOC has exhibited two states: a strong, stable state and a slow, weak one. Warming temperatures weaken the AMOC, the new analysis suggests, ultimately pushing it toward a tipping point where it could rapidly turn off.
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<img alt="This map of the Atlantic shows the direction the Gulf Stream travels as it transports warm water north from the equator" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/gulf-stream1.width-990_N5nBqXX.jpg"/>
<figcaption>The Gulf Stream is part of the Atlantic Meridional Overturning Circulation (AMOC), an Atlantic section of a global conveyor belt that drives surface and deepwater currents in every ocean, and influences the rate of sea ice formation at the poles. Image Credit: NOAA/JPL-Caltech
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Scientists hypothesize that such a shutdown may have occurred during the Younger Dryas. <a href="https://www.nature.com/articles/s41561-018-0169-6.epdf?sharing_token=F3sE8Eo9hOHZnYqD8YK7k9RgN0jAjWel9jnR3ZoTv0OX_eD6yrmH_7KKq-gygRSNxvqRGZfDf7DCL5eW-PfuvVeVS5aEtCzL4lRS0KXrvYe-24aRLXrqpLY9PKRR8pszYvChNUjQnC8PJGBB1IRUSURV1kNkXSchj5kFHdhB2udPaj7ghC_XFTmg7ke-eDC0SR1noiA_3Pf0AsrIuHsXUylW309RZffhMecEiWRknbQ%3D&amp;tracking_referrer=www.washingtonpost.com">As one theory goes</a>, as the planet warmed, glacial flood waters leaked into the Arctic and the North Atlantic, diluting the oceans’ saltiness, and weakening the AMOC. In addition, a massive ice sheet covering millions of miles—which helped contain an enormous glacial lake in what is now Canada—began to melt away. This triggered a freshwater flood, which traveled north up a river system and eventually emptied into the Arctic Ocean. This influx of fresh water ultimately decreased the salinity, and thus the density, of surface water in the northern Atlantic ocean to the point that it was no longer able to sink and make the return journey to the equator. So the AMOC shut down.Now, tens of thousands of years later,<a href="https://www.nature.com/articles/s41561-021-00699-z.epdf?sharing_token=fgt0vYw1E23vIb6z6zAzZNRgN0jAjWel9jnR3ZoTv0P93m6r2g6HCxEqjXwwP2zvNWm69miAlh1y_Z4SKXkP2NztMnWE6tMualAxgMFqr5BAxjwOlHhoLMeFCf0O_s1NN4HEUMLu7yNL5SvtNwdq4Qx78MVJ8W2EkmbQUfVnhfJ3ffV3HAA-WJn4cwtKnjyJnt5Q0NGn8v5HxLTpQFtiy9ur5aXEQwixPOLHKZ1qtGM%3D&amp;tracking_referrer=www.washingtonpost.com"> scientists have cautioned</a> that the AMOC is at its weakest point in over a millennium. But researchers have not been able to pinpoint how close the AMOC is to a total shutdown. Boer’s findings suggest a new insight: The AMOC’s decline may be indicative of an “almost complete loss of stability.”The new study’s primary findings are based on eight independent sea-surface temperature and salinity datasets spanning 150 years. Climate change is destabilizing the AMOC, Boers concludes, noting that the “restoring forces” that keep the AMOC functioning, such as temperature and salinity, have become more erratic.The stabilizing force of the AMOC is cold, salt-rich water, which sinks to the ocean floor and powers the circulation that keeps the AMOC in its “on” mode. Meanwhile, warming surface waters and fresh water from melting ice push the AMOC away from stability.Boers analyzed how fast the sea surface temperature was returning to its state of equilibrium and how big the deviations from this state were becoming. Boer’s results indicate that the strength of the stabilizing current is declining and that an AMOC tipping point—an ecological point of no return that once crossed could take hundreds of years to stabilize—is much closer than previously understood.“The signs of destabilization being visible already is something that I wouldn’t have expected and that I find scary,” Boers told <a href="https://www.theguardian.com/environment/2021/aug/05/climate-crisis-scientists-spot-warning-signs-of-gulf-stream-collapse">The Guardian</a>. “It’s something you just can’t [allow to] happen.”But a result of this magnitude needs to be tested by other researchers before it is widely accepted, Foukal says.
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As carbon dioxide accumulates in Earth’s atmosphere, the atmosphere and ocean trap more heat. As global temperatures rise, they trigger more glacial ice to melt. An influx of freshwater into the North Atlantic from the Greenland ice sheet will reduce the North Atlantic’s salinity and density, making the water lighter and less able to sink. In addition, warmer temperatures cause water molecules to spread farther apart, making the ocean waters even less dense. Similar to what happened during the Younger Dryas, if the water in the North Atlantic is not heavy enough to sink, the entire AMOC will shut down, Boers explains.In its 2019 “<a href="https://www.ipcc.ch/srocc/chapter/summary-for-policymakers/">Special Report on the Ocean and Cryosphere in a Changing Climate</a>,” the United Nations Intergovernmental Panel on Climate Change (IPCC) stated that the AMOC is “very likely” to weaken due to climate change. But a total shutdown within the next 300 years, the report states, is only likely under a worst-case carbon dioxide emissions scenario with global average temperatures rising by 4.3 degrees Celsius by the end of the century.Still, Boers’ findings suggest that “the critical threshold is most likely much closer than we would have expected,” he says.<h3>The implications of a weakening AMOC</h3>Should the<a href="https://www.ipcc.ch/srocc/chapter/summary-for-policymakers/"> AMOC weaken substantially</a>, it could “drastically” affect rainfall patterns in tropical monsoon systems, Boers told NOVA.Monsoons supply water to many parts of the world. Yackar Mauzole, an oceanographer whose research focuses on the Indian Ocean, points out that if the amount of precipitation and location of monsoon systems were to change, it would have major implications for the Maldives, India, Thailand, and other populous countries that rely on monsoons for agriculture.Weakening of the AMOC could also bring less summer rainfall to South Asia and the <a href="https://theconversation.com/sahel-region-africa-72569">Sahel</a>, the semiarid African region stretching from Senegal to Sudan that receives much of its rainfall from the West African monsoon, the <a href="https://www.ipcc.ch/srocc/chapter/summary-for-policymakers/">IPCC projects</a>.“A change in monsoon systems would have severe consequences for the populations living in these regions,” Mauzole says. “Beyond oceanography and climate science, food insecurity should be something to consider if the AMOC were to transition in the future.”
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<img alt="The Maldives is on the front lines of climate change" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/AMOC_Body_Image.width-990_wuvtGuk.jpg"/>
<figcaption>A man operates a pump to try and clear flooded drains during torrential rain in December 2019 in the Maldives, the world's lowest-lying country. Image Credit: Carl Court/Getty Images
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To better assess what may happen in the future, some scientists are looking to the past. The AMOC shutdown 13,000 years ago led to an abrupt cooling of North America and Europe that lasted 1,000 years, they believe.<a href="https://www.pnas.org/content/109/13/4730"> Archaeological analyses</a> of skeletal remains and plant fossils from modern-day Syria and the Nile Valley suggest that the climatic shock of the Younger Dryas upended early human settlements, causing conflict, starvation, drought, and malnutrition, and led to the collapse of several agricultural civilizations.Today, as climate change <a href="https://www.carbonbrief.org/guest-post-could-the-atlantic-overturning-circulation-shut-down">destabilizes the delicate balance</a> of temperature and salinity the AMOC relies on, some scientists worry that the AMOC is already showing symptoms of decline. “It’s as though the AMOC is a patient newly arrived in the emergency room, and Boers has provided scientists with an assessment of its vital signs,” Woods Hole Oceanographic Institution President Peter de Menocal told <a href="https://www.washingtonpost.com/climate-environment/2021/08/05/change-ocean-collapse-atlantic-meridional/">The Washington Post</a> in August. “All the signs are consistent with the patient having a real mortal problem.”But the size and complexity of the AMOC system offer some hope: It will take time, close monitoring, and meticulous data collection before researchers are able to confirm an AMOC slowdown through direct observations, Foukal notes. Many realize the risk of waiting for evidence of a collapse.“The possibility that the AMOC tipping point is close should motivate us to try to stop it from happening. If we surpass a tipping point it could affect us for hundreds of years,” says Levke Caesar, a climate physicist at Maynooth University in Ireland who was not involved in the study. Research by Caesar <a href="https://www.nature.com/articles/s41561-021-00699-z.epdf?sharing_token=fgt0vYw1E23vIb6z6zAzZNRgN0jAjWel9jnR3ZoTv0P93m6r2g6HCxEqjXwwP2zvNWm69miAlh1y_Z4SKXkP2NztMnWE6tMualAxgMFqr5BAxjwOlHhoLMeFCf0O_s1NN4HEUMLu7yNL5SvtNwdq4Qx78MVJ8W2EkmbQUfVnhfJ3ffV3HAA-WJn4cwtKnjyJnt5Q0NGn8v5HxLTpQFtiy9ur5aXEQwixPOLHKZ1qtGM%3D&amp;tracking_referrer=www.washingtonpost.com">conducted in 2021</a> shows the AMOC is at its weakest point in over 1,000 years.Climate scientists are still unsure what threshold of carbon dioxide in the atmosphere would cause the AMOC to shut down. “The only thing to do is keep emissions as low as possible,” Boers told The Guardian. “The likelihood of this extremely high-impact event happening increases with every gram of CO2 that we put into the atmosphere.”
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New evidence suggests that the larger system the Gulf Stream is part of is approaching a tipping point that could cause dramatic shifts in global weather patterns.

A sculpture of James Marion Sims. Often “portrayed as a champion of women’s health,” this 19th-century “father of modern gynecology” developed many of his techniques by conducting unethical research and experiments on enslaved Black women. Image Credit: Matt Green/Flickr/CC BY-NC-SA 2.0

Where Science and Social Justice Meet

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As communities across the country grapple with the legacy of institutional racism, many educators are evaluating the role they can play in addressing systemic racism. One way to begin doing this is by making a conscious effort to become educated about the history that has shaped this country — including the history of science — and acknowledging the ways in which racial inequities continue to exist and shape society. NOVA is committed to providing educators with resources to address the racial inequities that impact students. This fall, NOVA Education has organized a three-part speaker series dedicated to discussing the intersection of STEM education and social justice.
<h3>The History of Scientific Racism (and Why it Matters for STEM Educators)</h3>
Tuesday, October 20, 2020 6PM ET / 3PM PT Watch Here: <a href="https://youtu.be/-XptxJoE7mU">NOVA Education YouTube</a>
Historically, science has been conceptualized as objective, neutral, and apolitical. In reality, however, it is not. Science is carried out by real people and, thus, can be shaped by their beliefs, social values, and biases. In this talk, <a href="http://udodiriokwandu.com/">Udodiri R. Okwandu</a> discusses the histories of unethical medical and scientific practices used in America from the 19th century to the present to demonstrate how science has and continues to perpetuate racism and inequality in society. In tracing this history, we hope that this webinar will empower STEM educators to account for gaps in science education in order to engage in more equitable and anti-racist pedagogy.To learn more about the history of scientific racism and how to talk about it with your students, check out <a href="https://docs.google.com/document/d/1uNA24QfbTWlQ0T4rACgk_tOgj4I7wr08fZDVad-3B08/edit?usp=sharing">this list of resources</a>.
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<h3>History Reconsidered</h3>
Wednesday, October 28, 2020 6PM ET / 3PM PT Watch Here: <a href="https://www.youtube.com/watch?v=c1K44BwdhrE">NOVA Education YouTube</a>
The second installment of the webinar series will feature a talk from <a href="https://www.clintsmithiii.com/about">Dr. Clint Smith</a>, a writer, poet and scholar who will help educators wrestle with the complicated truths about the country we live in. In many K-12 education settings, the United States is lauded as a country of great opportunity and economic mobility. However, to engage US history truthfully and accurately means we must interrogate how the US history of violence and exploitation helped generate its economic foundations. These realities shape the lives of our students, and the landscapes of our schools. In this talk, combining poetry and history, Dr. Clint Smith will help crystalize how this history has shaped the contemporary social, political, and cultural context of our world today — specifically our schools — and how to talk about it with your students.<div>
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<h3>Bringing a Justice Orientation to K-12 STEM Teaching &amp; Learning</h3>
Tuesday, November 10, 2020 6PM ET / 3PM PT Watch Here: <a href="https://www.youtube.com/watch?v=iR5QrsXAGo8&amp;t=1s">NOVA Education YouTube</a>
The final science and social justice webinar will include a presentation from <a href="https://soe.uncg.edu/directory/faculty-and-staff/bio-ednatan/">Dr. Edna Tan</a>, professor of science education at the University of North Carolina at Greensboro, and <a href="https://soe.umich.edu/directory/faculty-staff/angela-calabrese-barton">Dr. Angie Calabrese Barton</a>, professor in the Educational Studies Department at the University of Michigan. Calls to increase equity in teaching and learning are often framed only around inclusion — ensuring that learning opportunities are available for all students. Unfortunately, this perspective of equity is limiting and does not adequately address how systemic injustices manifest in classroom practice and impact student learning. In this workshop, Dr. Edna Tan and Dr. Angela Calabrese Barton will share a justice-oriented framework that highlights how STEM educators can make connections to the realities and issues that guide students’ lives, sharing case studies drawn from formal and informal STEM teaching and learning.<div>
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Join NOVA Education for three virtual events dedicated to the intersection of STEM education and social justice.

Cristina Mittermeier on-assignment in the Yucatán Peninsula. Image Credit: Jenny Nichols

Interview: National Geographic marine life photographer Cristina Mittermeier

World-renowned photographer Cristina Mittermeier explains her philosophy behind conservation photography, mentorship, and the increased diversity she would like to see within the environmental movement.

Confiscated wildlife ends up in the National Wildlife Property Repository, a 22,000 square foot warehouse near Denver, Colorado that houses wildlife items that have been forfeited or abandoned to the U.S. Fish and Wildlife Service. Image Credit: Ryan Moehring / USFWS National Digital Library

The 21st Century Threat to Wildlife is "Cyberpoaching"

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In July 2013, Krishnamurthy Ramesh, head of the monitoring program at Panna Tiger Reserve in central India, received a security alert. Someone was attempting to access his email account from a location more than<a href="https://www.nationalgeographic.com/news/2013/10/131010-poaching-technology-tigers-endangered-animals-science/"> 600 miles away from his office</a>. Sitting in Ramesh’s inbox was an email reporting the encrypted coordinates of an endangered Bengal tiger.
Tigers are considered “walking gold” on the black market. Although leading Traditional Chinese Medicine (TCM) organizations have <a href="https://bit.ly/3jGDvgg">banned the use of tiger parts</a>, a robust illegal market that values tigers as luxury items—particularly their bones and pelts—still exists.
However, the demand for wildlife products is not limited to tigers. Elephants, rhinos, pangolins, sharks, and many other species are part of this massive illicit trade. The world of wildlife trafficking and poaching is orchestrated by highly organized crime syndicates which rake in profits<a href="https://www.interpol.int/en/Crimes/Environmental-crime/Wildlife-crime"> exceeding $20 billion</a> per year. It is the fourth most profitable illegal enterprise behind<a href="https://www.unodc.org/unodc/en/corruption/wildlife-and-forest-crime.html"> narcotics, weapons, and human trafficking</a>, and is considered a significant contributor to the<a href="https://www.pnas.org/content/117/24/13596"> sixth mass extinction</a>.

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<figcaption>Less than 4,000 tigers remain in the wild. Image courtesy of the International Fund for Animal Welfare (IFAW) 
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Although the suspicious log-in attempt was thwarted by Ramesh’s server, and the tiger’s exact location was encrypted, the cybersecurity breach exposed the threat of an endangered animal’s GPS coordinates falling into the wrong hands.
Today, emails are encrypted by <a href="https://www.youtube.com/watch?v=q6FanLhvsEs">coded email programs</a> to prevent others from reading them. However,<a href="https://mass.pbslearningmedia.org/resource/nvcy-sci-cybercodes/cyber-codes/"> not all online activity is encrypted</a> and in some cases browsing history, text messages, and data from apps can be intercepted. Emails are normally encrypted when they are sent, but can sometimes be decrypted before they reach their recipient. Cybersecurity news often focuses on how hackers access personal information, bank accounts, social media, and government data. But what if “cyberpoachers” started targeting information on the locations of endangered species through their animal tracking data?
<h2>The Rise of Wildlife Cybercrime</h2>
The illegal wildlife trade has transformed with the growth and accessibility of the internet. Animals that used to be sold in physical markets are now sold by <a href="https://www.ifaw.org/press-releases/tech-companies-wildlife-trafficking-online">anonymous online vendors</a>. As a result, a largely<a href="https://www.ifaw.org/journal/hot-on-the-trail-of-cyber-enabled-wildlife-traffickers"> unregulated online market</a> allows criminal enterprises to sell illegally acquired wildlife products, and transport them around the world. The consumer-to-consumer marketplace has made buying shark fins, pangolin scales, and rhino horns as easy as click, pay, ship.

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<figcaption>Infographic courtesy of IFAW
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The 2018 International Fund for Animal Welfare (IFAW) report <a href="https://www.ifaw.org/resources/disrupt-wildlife-cybercrime">Disrupt: Wildlife Cybercrime</a> identified more than 5,000 advertisements spread across more than 100 online marketplaces and social media platforms, cataloguing close to 12,000 endangered and threatened specimens worth almost $4 million. These items were completely accessible to the public; the report did not include items advertised in closed or private Facebook groups, password-protected websites, or the hidden part of the internet—the <a href="https://www.imf.org/external/pubs/ft/fandd/2019/09/the-truth-about-the-dark-web-kumar.htm">dark web</a>.
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“Many of the species preyed upon by wildlife criminals are in danger of approaching a tipping point where their diminishing numbers can no longer sustain their populations,” described Rikkert Reijnen, program director of wildlife crime at IFAW, in the Disrupt report. “Some, such as rhinos, may have already reached that point. Disrupting wildlife cybercrime is a critical component of ensuring the welfare, safety and survival of endangered and threatened animals.”

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<figcaption>A wildlife ranger stands guard as towers of confiscated ivory go up in smoke in Kenya's Nairobi National Park. The country burned 105 tons of ivory in 2016 to send a stern message: Ivory is worthless unless it is on elephants. Image courtesy of IFAW
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Unfortunately, illegal online markets aren’t the only “digital threat” to endangered wildlife. In recent years, hackers have exploited the very systems designed to monitor and protect these animals. By decrypting location data from radio tags and GPS collars, hackers can track down animals or reveal their whereabouts to those who would harm them. (Hacking by nature is not good or bad—it is essentially solving problems in creative and innovative ways. Some hackers use questionable methods of acquiring information, whether with intent to help or harm, while others use hackathons to improve existing security protocols by collaborating as a community to solve complex problems.)
“Being able to put on a map exactly where animals are in space in time, that’s what one needs to exploit them,” wrote Steven J. Cooke, a biology professor at Carleton University in Canada, in an article in the journal <a href="http://www.fecpl.ca/wp-content/uploads/2016/12/Cooke_et_al-2017-Conservation_Biology-1.pdf">Conservation Biology</a>.
Cooke pointed out that the animal-tracking data scientists use to safeguard animals could potentially be used to harm them by poachers, commercial fishermen, and even nature lovers looking to photograph them.
Some of the troubling ways radio tags and collars have been used to “locate, disturb, capture, harm, or kill tagged animals,” Cooke pointed out, include<a href="https://www.theguardian.com/environment/2015/jan/14/researcher-threatens-withhold-information-wa-killing-tagged-sharks"> great white sharks</a> that were killed in Western Australia by individuals who had tracked their radio signals to “reduce human-wildlife conflict,” as well as efforts by “wolf persecution” groups to decrypt data on radio collars to allow them to<a href="https://www.outsideonline.com/1913831/out-bounds-death-832f-yellowstones-most-famous-wolf#close"> hunt down and kill wolves</a> in Yellowstone National Park.

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<figcaption>A wolf watches biologists in Yellowstone National Park after being captured and fitted with a radio collar. Image Credit: William Campbell / USFWS National Digital Library 
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According to wildlife criminologist Monique Sosnowski, there are two primary ways poachers can attempt to access animal tracking data.
“First, they can attempt to bribe corrupt individuals such as anti-poaching entities or game guides charged with locating and protecting these species,” Sosnowski says.
When it comes to infiltrating the tracking systems themselves, Sosnowski notes that this requires more technical skill and is thus more likely attempted by organized criminal networks.
“Cases of this have been reported around the world as poachers have attempted to gain access to GPS data, or capitalize on VHF radio signals,” she says.
Tarah Wheeler, an international security fellow at New America, highlighted a third way “cyberpoachers” can track wild animals. If the location setting on your cell phone is switched on when snapping a photo of an animal, that data is embedded in the photo you post on social media, creating a<a href="https://mass.pbslearningmedia.org/resource/nvcy-sci-parable/a-cyber-privacy-parable/"> digital roadmap</a> for poachers to track wildlife.
“Because of the way cell phones track your location now, you don’t need to critique someone’s photograph to find out where they were at a given time,” Wheeler told <a href="https://www.nbcnews.com/business/business-news/your-safari-selfies-are-cute-they-re-road-map-poachers-n1016031">NBC News</a>. “Metadata, including exact longitude and latitude, is stuck to the background of the photo.”
<h2>Hack the Poacher</h2>
Just as poachers might access animal tracking data through vacation selfies posted from a smartphone, <a href="https://hack-the-planet.io/">Hack the Planet</a> software engineers Tim van Deursen and Thijs Suijten have leveraged mobile phones to create a detection system to turn the tables on poachers.
Van Deursen and Suijten designed the <a href="https://www.hackthepoacher.com/">Hack the Poacher</a> system with the intent to deter poachers from protected areas and aid rangers in their ongoing fight against wildlife crime. The system uses sensors placed throughout the target area to detect poacher’s GSM cell phone signals as well as radio frequencies so rangers that patrol poaching hotspots can be alerted to their presence. Hack the Poacher works with individual parks to tailor their technology to the issues that rangers are seeing on the ground in specific poaching hotspots.

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<figcaption>In Zambia, where the Hack the Poacher system has been tested, poachers rely heavily on their mobile phones and radios for navigation and communication with each other to coordinate and organize extraction of ivory. Illustration courtesy of Hack the Poacher.
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“When your cell phone is on, it's always searching for GSM towers,” Suijten says. “The rangers at the park we are working with in Zambia told us that poachers always have a phone on them. Even if there is no GSM coverage, if their cell phone is on, it will always be searching for a cell phone tower and transmitting a strong signal to connect to service.”
The Hack the Poacher system can monitor up to 300 square kilometers (115 square miles) with just 30-40 sensors. The founders believe this system could eventually work in tandem with other tech tools like automated camera traps, machine learning, and satellite imagery, sending rangers alerts in real time and keeping them steps ahead of poachers.
“Many initiatives in the past focused on optimizing detection of poachers by trying to get eyes on the poacher with, for example, the use of drones, night vision cameras, radar, and satellites,” van Deursen says. “While these techniques can be effective, the costs are often too high to implement on a large scale, or too technologically advanced to be operated by people other than the tech team behind the product.”
Hack the Poacher is powered by three agencies:<a href="https://hack-the-planet.io/"> Hack the Planet</a>,<a href="https://www.q42.nl/en"> Q42</a>, and <a href="https://www.irnas.eu/">Irnas</a>. These strategic technology companies work on creating and implementing pragmatic technologies to tackle humanitarian and sustainability challenges. The Hack the Poacher project has also received support from World Wildlife Fund (WWF), Google, Green Safaris, No Wildlife Crime (NWC), and Smart Parks.
<h2>Using Radical Collaboration to Save Wildlife</h2>
Just as Hack the Poacher is working to stop poaching at its source, IFAW is working alongside the world’s largest e-commerce, technology, and social media companies to shut down online marketplaces that deal in the trade of illegal wildlife.
“Within IFAW, we have a lot of innovative and unique partnerships that we leverage to address cybercrime and analyze data related to wildlife trafficking,” says Danielle Kessler, acting US director of IFAW. “We are working through the <a href="https://www.worldwildlife.org/pages/coalition-to-end-wildlife-trafficking-online">Coalition to End Wildlife Trafficking Online</a> to collaborate with 36 tech companies across continents, such as eBay, Google, Microsoft and Tencent, to unite the industry and maximize impact for reducing wildlife trafficking online.”

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<figcaption>African elephants are the largest land animals on Earth and could be extinct in the next decade. Poachers kill an estimated 55 elephants a day. Image courtesy of IFAW
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When it comes to finding solutions at the nexus of wildlife crime and cybersecurity, hackathons provide opportunities for students to invent and innovate new technology for the good of the planet. This November, the Department of State is co-hosting<a href="http://www.zoohackathon.com/"> Zoohackathon</a> 2020, a global competition bringing together university students, coders, developers, and wildlife trafficking experts to create innovative solutions that address on-the-ground wildlife trafficking issues. Over the course of two and a half days, participants from five regional areas across the globe will compete virtually to address wildlife trafficking challenges, analyze the connections between wildlife trafficking and zoonotic disease in each region, and discuss locally focused case studies.
For Suijten, a focus on hard skills such as software engineering are critical, but relationship building and the ability to adapt and respond to circumstances in the field have proven to be invaluable to Hack the Poacher’s success.
“It’s amazing how much impact we can have with smart engineers, pragmatic tech, and a bit of duct tape,” Suijten says.
As people’s lives become more intertwined with the internet, the opportunities in cybersecurity continue to expand. To learn more about this growing field, visit the <a href="https://www.pbs.org/wgbh/nova/labs/lab/cyber/">NOVA Cybersecurity Lab</a> to explore stories of real-world cyber attacks, profiles of cybersecurity experts, and short animated videos that explain the need for cybersecurity, privacy versus security, cryptography (cyber code), and the nature of hacking.
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The growth and accessibility of the internet has transformed the illegal wildlife trade.

Grapefruit-mint-marmalade chocolate lava mini cakes with fresh mint ricotta. Image Credit: Annie Wu

Bring the Science of Taste into the Classroom with NOVA Resources

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In early April, Annie Wu, a professional musician, began experiencing COVID-19 symptoms. During her self-imposed quarantine, Wu developed a symptom that an <a href="https://www.scientificamerican.com/article/mysteries-of-covid-smell-loss-finally-yield-some-answers1/">estimated 80%</a> of people who contract COVD-19 report: anosmia, the loss of the sense of smell. Soon, she also experienced a loss of taste (ageusia). She remembers biting into a celery stick slathered in peanut butter and tasting nothing at all. “It was jarring, peanut butter tasted like tacky Elmer’s glue, coffee became warm dirt water,” she says.
Wu has since recovered from COVID-19, but has yet to fully regain her senses of smell and taste. Rather than dwell on this loss, the experience has transformed the way she connects with and thinks about food. Over the course of the past seven months, she has chronicled her journey online with her Instagram account “in search of lost smell”<a href="https://www.instagram.com/insearchoflostsmell/"> (@insearchoflostsmell</a>).
As the months passed, smell maintained an elusive haze, but Wu’s taste began to sharpen as she ventured out of her comfort zone. Rather than dwell on what she was lacking, she started experimenting with flavor profiles that she had previously avoided. “There was a world of flavor to explore—vinegars, sugary glazes, citrus, fermented goods,” she says. “Taste can carry with it memories, reactions, and even excitement for the future.”

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<figcaption>Vanilla skyr-stuffed persimmon with honey and pistachios. Image Credit: Annie Wu
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“Food’s ability to connect you to something so specific, and yet so collective, is amazing,” Wu says.
Through this process, Wu realized that smell is not just the firing of tingly nerves in our noses, but a connection to rapture, delight, and discovery. By sharing photos of her visually stimulating new meals with strangers on social media, she was surprised by the connections that she was able to develop with chefs who inspire her, teachers at food justice programs, food lovers from all over the world, and even those who had lost their own sense of smell and taste as well.
Throughout her experience chronicling the various recipes she is testing and sharing on social media, she has received descriptive messages about the way that various ingredients taste, with respondents often connecting flavor profiles to a feeling, certain memories, or a particular place that it reminds them of.
“You forget how much smell ties to these emotional parts of your life, like walking into your family childhood home,” Wu says.
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Which raises the question, what is the biological connection between smell, taste, and memory?
Within the human nose, there are more than 12 million smell receptors (of about <a href="https://www.sciencedaily.com/releases/2019/04/190430164208.htm">400 different types)</a>, which are activated by millions of potential combinations of odor molecules. The receptors detect odor molecules and send information back to the olfactory bulb in the brain, where these scents are interpreted. The olfactory system is closely linked with the temporal lobe, which is responsible for emotion and memory.

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<figcaption>All five senses play a role in experiencing the flavor of food. Image Credit: NOVA: Can I Eat That? | The Science of Flavor
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This area of the brain is also home to the amygdala and hippocampus, which are critical for emotional learning, memory, and smell. This connection explains why <a href="https://harvardpress.typepad.com/hup_publicity/2012/05/food-and-memory-john-allen.html#:~:text=The%20taste%2C%20smell%2C%20and%20texture,of%20the%20mind%20and%20body.">certain smells may trigger vivid memories about past events</a>. The hippocampus is also linked to our digestive system which helps regulate appetite, digestion, and eating behavior. Finding food was so critical to our survival as a species that scientists believe our brains evolved to form memories about and around food—<a href="https://www.sciencedirect.com/science/article/pii/S0960982213004181">including those that make us sick</a>.
But what is it specifically about novelty candies, family recipes, or holiday dishes that make them so memorable after many years? When we eat highly appealing foods, such as chocolate, the neurotransmitter dopamine is released. This triggers the reward center of our brain and, when transmitted via the hippocampus, <a href="https://www.sciencedaily.com/releases/2013/08/130825171530.htm">dopamine helps turn short-term memories into long-term ones</a>.
This explains why our attraction to, or disgust with, certain foods lasts for years after tasting them. It is because of the connections between the olfactory system and regions of the brain responsible for emotion and memory that <a href="https://www.livescience.com/why-smells-trigger-memories.html">positive or negative flavor experiences</a> can be long lasting.
With the holidays just around the corner, cherished family recipes and delectable side dishes are on everyone’s mind. Use these NOVA resources to introduce students to neuroscience, chemistry, and biology concepts that explain the science behind flavor, and how smell, sight, and sound can influence the experience.
<h2>NOVA Resources on PBS LearningMedia</h2>
 <a href="https://mass.pbslearningmedia.org/resource/nvsn6.sci.bio.flavor/the-science-of-flavor/">NOVA: Can I Eat That? | The Science of Flavor</a>Learn more about the perception of flavor, and how dulling a person’s ability to smell can make something taste flavorless. Use this NOVA scienceNow resource to show students which parts of the body can help you experience flavor, how looks can be deceiving when tasting food items, and how sound provides information about food.
<a href="https://mass.pbslearningmedia.org/resource/nvsn6.sci.bio.taster/what-is-a-supertaster/">NOVA: Can I Eat That? | What is a Supertaster?</a>This video breaks down the science of taste buds and explains how the number of taste buds you have can affect the way that you interpret certain flavors. Learn why some people experience taste more intensely than others, and what evolutionary advantages "supertasters" have developed.
<a href="https://mass.pbslearningmedia.org/resource/nvsn6.sci.chem.turkey/the-chemistry-of-tender-turkey/">The Chemistry of Tender Turkey</a>Learn about the chemistry behind brining meat. Correspondent and New York Times technology columnist David Pogue explores how the process of brining can ensure a tender and moist cooked turkey. Use this NOVA scienceNOW resource to demonstrate how soaking a raw turkey in salt water adds moisture to the meat through the process of osmosis, and watch as Pogue participates in a taste test to identify samples of turkey cooked with and without brining.
<h2>NOVA Digital Resources</h2>
 <a href="https://www.pbs.org/wgbh/nova/video/anosmia-coronavirus-screenings/">How Anosmia Could Affect Doctors’ Coronavirus Screenings</a>Learn more about the symptom that an estimated 80% of COVID-19 patients report experiencing. Use this NOVA video to help unpack the science behind how COVID-19 can cause smell loss and whether the condition is permanent.
<a href="https://www.pbs.org/wgbh/nova/video/turn-to-science-for-great-thanksgiving-stuffing/">Turn to Science for Great Thanksgiving Stuffing</a>What makes onions so oniony? Why does stuffing sometimes come out gummy? Learn the secret to making delicious stuffing with the perfect texture—and why chemical reactions and volatile molecules in onions might make you cry as you cut them.
<a href="https://www.pbs.org/wgbh/nova/podcast/">NOVA Now Podcast: The Future of Food</a>In honor of celebrating nature’s bounty, NOVA Now podcast host Alok Patel considers the past, present, and future of food. He digs into the world of food science with the resident science guy at America’s Test Kitchen; speaks with an Indigenous community cook, educator, and community organizer about food sovereignty and equitable food systems; and checks in with a scientist who is genetically engineering plants to photosynthesize more efficiently to increase crop yields.
<h2>NOVA Science Café Resource</h2>
 <a href="https://www.youtube.com/watch?v=jk1Bgw8Tul8">Much Ado About Stuffing: Answering Your Thanksgiving Cooking Questions</a>With COVID-19 keeping friends and family apart, Thanksgiving celebrations will look different than in years past. Lan Lam, Senior Editor at Cook's Illustrated is here to answer all of your last minute Thanksgiving cooking questions—from the calculations to reduce recipe sizes to science-backed ways to get the most flavor from your food.
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Use these NOVA resources to introduce students to neuroscience, chemistry, and biology concepts that explain the science behind flavor, and how smell, sight, and sound can influence the experience.

The Tongass National Forest’s trees hold about 650 million tons of carbon, which convert to about half of U.S. carbon dioxide emissions in 2017. Image Credit: Phillip Gladkov

Tongass National Forest is 'America's Last Climate Sanctuary'

Opening up the Tongass National Forest to additional logging and development could have serious implications for both the environment and the Alaska Native communities that depend on it.

Kara Norton

Articles