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2020 ties for hottest year on record, says NASA and NOAA
In a joint briefing at the 101st American Meteorological Society Annual Meeting, NASA and NOAA revealed 2020's scorching climate data.

You may have noticed a trend in the last few years. At the beginning of every year, NASA and NOAA share their analyses of the previous year's climate data. And every year, their data reveal the previous year to be one of the hottest on record—with 2016 at the torrid top of 139 years of documentation. That's no coincidence. Climate change is happening, it's happening now, and it's human-caused.
That's the consensus of 97 percent of climate scientists, according to a 2014 report from the American Association for the Advancement of Science. That's the same percentage of physicians and cardiovascular scientists who agree that smoking causes lung cancer, and it's a consensus reached through decades worth of surveys and studies into the realities and causes of climate change.
Now, climate scientists have two more analyses to add to their overwhelming evidence. In a briefing at this year's 101st American Meteorological Society Annual Meeting, representatives for NASA and NOAA revealed their independent analyses of 2020's climate data. And the trend continues.
A dead heat
A graph showing the global mean temperatures from 1880–2020 (with the years 1951–1980 serving as the mean baseline).
Credit: NASA and NOAA
For its 2020 analysis, NASA gathered surface temperature measurements from more than 26,000 weather stations. This data was incorporated with data from satellites as well as sea-surface temperatures taken from ship and buoy instruments. Once tallied, NASA's data showed 2020 barely edged out 2016 as the warmest year on record, with average global temperatures 1.02°C (1.84°F) above the baseline mean (1951-1980).
In a separate analysis of the raw data, NOAA found 2020 to be slightly cooler than 2016. This distinction is the result of the different methodologies used in each—for example, NOAA uses a different baseline period (1901–2000) and does not infer temperatures in polar regions lacking observations. Together, these analyses put 2020 in a statistical dead heat with the sweltering 2016 and demonstrate the global-warming trend of the past four decades.
"The last seven years have been the warmest seven years on record, typifying the ongoing and dramatic warming trend," Gavin Schmidt, director of the NASA Goddard Institute for Space Studies, said in a release. "Whether one year is a record or not is not really that important—the important things are long-term trends. With these trends, and as the human impact on the climate increases, we have to expect that records will continue to be broken."
And they are. According to the analyses, 2020 was the warmest year on record for Asia and Europe, the second warmest for South America, the fourth warmest for Africa and Australia, and the tenth warmest for North America.
All told, 2020 was 1.19°C (2.14°F) above averages from the late-19th century, a period that provides a rough approximate for pre-industrial conditions. This temperature is closing in on the Paris Climate Agreement's preferred goal of limiting global warming to 1.5°C of those pre-industrial conditions.
2020's hotspot was—the Arctic?
A map of global mean temperatures in 2020 shows an scorching year for the Arctic.
(Photo: NASA and NOAA)
Heatwaves have become more common all over the world, but a region that really endured the heat in 2020 was the Arctic.
"The big story this year is Siberia; it was a hotspot," Russell Vose, chief of the analysis and synthesis branch of NOAA's National Centers for Environmental Information, said during the briefing. "In May, some places were 18°F above the average. There was a town in Siberia […] that reported a high temperature of 104°F. If that gets verified by the World Metrological Organization, it will the first there's been a weather station in the Arctic with a temperature above 100°F."
The Arctic is warming at three times the global mean, thanks to a phenomenon known as Arctic Amplification. As the Arctic warms, it loses its sea ice, and this creates a feedback loop. The more Arctic sea ice loss, the more heat introduced into the oceans; the more heat introduced, the more sea ice loss. And the longer this trend continues, the more devastating the effects.
For example, since the 1980s, there's been a 50 percent decline in sea ice, and this loss has exposed more of the ocean to the sun's rays. That energy then gets trapped in the ocean as heat. As the ocean heat content rises, it threatens rising sea levels and the sustainability of natural ecosystems. In 2020 alone, 255 zeta joules of heat above the baseline were introduced into Earth's oceans. In (admittedly) dramatic terms, that's the equivalent of introducing 5 to 6 Hiroshima atom bombs worth of energy every second of every day.
Looking beyond the Arctic, the average snow cover for the Northern Hemisphere was also the lowest on record. Like the Arctic sea ices, such snow cover helps regulate Earth's surface temperatures. Its melt off in the spring and summer also provides the freshwater ecosystems rely on to survive and farmers need to grow crops, especially in the Western United States.
Natural disasters get a man-made bump
A map of 2020's billion-dollar weather and climate disasters, which totaled approximately $95 billion in losses.
Credit: NASA and NOAA
2020 was also a record-breaking year for natural disasters. In the U.S. alone, there were 22 billion-dollar disasters, the most ever recorded. Combined, they resulted in a total of $95 billion in losses. The western wildfires alone consumed more than 10 million acres and destroyed large portions of Oregon, Colorado, and California.
The year also witnessed a record-setting Atlantic Hurricane season with more than 30 named storms, 13 of which were hurricanes. Typically, the World Meteorological Organization names storms from an annual list of 21 selected names—one for each letter of the alphabet, minus Q, U, X, Y, and Z. For only the second time in history, the Organization had to resort to naming storms after Greek letters because they ran out of alphabet.
For the record, there's a consensus about the record
Such records are a dramatic reminder of climate change's ongoing effect on our planet. They make for an eye-catching headline, sure. But those headlines can sometimes mask the fact that these years are part of decade-long trends, trends providing a preview of what a climate-changed world will be like.
And in case there was any question as to whether these trends were the result of natural processes or man-made conditions, Schmidt and Vose did not mince words.
As Schmidt said in the briefing: "Many, many things have caused the climate to change in the past: asteroids, wobbles in the Earth's orbit, moving continents. But when we look at the 20th century, we can see very clearly what has been happening. We know the continents have not moved very much, we know the orbit has not changed very much, we know when there were volcanoes, we know what the sun is doing, and we know what we've been doing."
He continued, "When we do an attribution by driver of climate change over the 20th century, what we find is that the overwhelming cause of the warming is the increase of greenhouse gases. When you add in all of the things humans have done, all of the trends over this period are attributable to human activity."
The data are in; the consensus is in. The only thing left is to figure out how to prevent the worst of climate change before it's too late. As bad as 2020 was, it was only a preview of what could come.
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How tiny bioelectronic implants may someday replace pharmaceutical drugs
Scientists are using bioelectronic medicine to treat inflammatory diseases, an approach that capitalizes on the ancient "hardwiring" of the nervous system.
Left: The vagus nerve, the body's longest cranial nerve. Right: Vagus nerve stimulation implant by SetPoint Medical.
- Bioelectronic medicine is an emerging field that focuses on manipulating the nervous system to treat diseases.
- Clinical studies show that using electronic devices to stimulate the vagus nerve is effective at treating inflammatory diseases like rheumatoid arthritis.
- Although it's not yet approved by the US Food and Drug Administration, vagus nerve stimulation may also prove effective at treating other diseases like cancer, diabetes and depression.
The nervous system’s ancient reflexes
<p>You accidentally place your hand on a hot stove. Almost instantaneously, your hand withdraws.</p><p>What triggered your hand to move? The answer is <em>not</em> that you consciously decided the stove was hot and you should move your hand. Rather, it was a reflex: Skin receptors on your hand sent nerve impulses to the spinal cord, which ultimately sent back motor neurons that caused your hand to move away. This all occurred before your "conscious brain" realized what happened.</p><p>Similarly, the nervous system has reflexes that protect individual cells in the body.</p><p>"The nervous system evolved because we need to respond to stimuli in the environment," said Dr. Tracey. "Neural signals don't come from the brain down first. Instead, when something happens in the environment, our peripheral nervous system senses it and sends a signal to the central nervous system, which comprises the brain and spinal cord. And then the nervous system responds to correct the problem."</p><p>So, what if scientists could "hack" into the nervous system, manipulating the electrical activity in the nervous system to control molecular processes and produce desirable outcomes? That's the chief goal of bioelectronic medicine.</p><p>"There are billions of neurons in the body that interact with almost every cell in the body, and at each of those nerve endings, molecular signals control molecular mechanisms that can be defined and mapped, and potentially put under control," Dr. Tracey said in a <a href="https://www.youtube.com/watch?v=AJH9KsMKi5M" target="_blank">TED Talk</a>.</p><p>"Many of these mechanisms are also involved in important diseases, like cancer, Alzheimer's, diabetes, hypertension and shock. It's very plausible that finding neural signals to control those mechanisms will hold promises for devices replacing some of today's medication for those diseases."</p><p>How can scientists hack the nervous system? For years, researchers in the field of bioelectronic medicine have zeroed in on the longest cranial nerve in the body: the vagus nerve.</p>The vagus nerve
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTYyOTM5OC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY0NTIwNzk0NX0.UCy-3UNpomb3DQZMhyOw_SQG4ThwACXW_rMnc9mLAe8/img.jpg?width=1245&coordinates=0%2C0%2C0%2C0&height=700" id="09add" class="rm-shortcode" data-rm-shortcode-id="f38dbfbbfe470ad85a3b023dd5083557" data-rm-shortcode-name="rebelmouse-image" data-width="1245" data-height="700" />Electrical signals, seen here in a synapse, travel along the vagus nerve to trigger an inflammatory response.
Credit: Adobe Stock via solvod
<p>The vagus nerve ("vagus" meaning "wandering" in Latin) comprises two nerve branches that stretch from the brainstem down to the chest and abdomen, where nerve fibers connect to organs. Electrical signals constantly travel up and down the vagus nerve, facilitating communication between the brain and other parts of the body.</p><p>One aspect of this back-and-forth communication is inflammation. When the immune system detects injury or attack, it automatically triggers an inflammatory response, which helps heal injuries and fend off invaders. But when not deployed properly, inflammation can become excessive, exacerbating the original problem and potentially contributing to diseases.</p><p>In 2002, Dr. Tracey and his colleagues discovered that the nervous system plays a key role in monitoring and modifying inflammation. This occurs through a process called the <a href="https://www.nature.com/articles/nature01321" target="_blank" rel="noopener noreferrer">inflammatory reflex</a>. In simple terms, it works like this: When the nervous system detects inflammatory stimuli, it reflexively (and subconsciously) deploys electrical signals through the vagus nerve that trigger anti-inflammatory molecular processes.</p><p>In rodent experiments, Dr. Tracey and his colleagues observed that electrical signals traveling through the vagus nerve control TNF, a protein that, in excess, causes inflammation. These electrical signals travel through the vagus nerve to the spleen. There, electrical signals are converted to chemical signals, triggering a molecular process that ultimately makes TNF, which exacerbates conditions like rheumatoid arthritis.</p><p>The incredible chain reaction of the inflammatory reflex was observed by Dr. Tracey and his colleagues in greater detail through rodent experiments. When inflammatory stimuli are detected, the nervous system sends electrical signals that travel through the vagus nerve to the spleen. There, the electrical signals are converted to chemical signals, which trigger the spleen to create a white blood cell called a T cell, which then creates a neurotransmitter called acetylcholine. The acetylcholine interacts with macrophages, which are a specific type of white blood cell that creates TNF, a protein that, in excess, causes inflammation. At that point, the acetylcholine triggers the macrophages to stop overproducing TNF – or inflammation.</p><p>Experiments showed that when a specific part of the body is inflamed, specific fibers within the vagus nerve start firing. Dr. Tracey and his colleagues were able to map these relationships. More importantly, they were able to stimulate specific parts of the vagus nerve to "shut off" inflammation.</p><p>What's more, clinical trials show that vagus nerve stimulation not only "shuts off" inflammation, but also triggers the production of cells that promote healing.</p><p>"In animal experiments, we understand how this works," Dr. Tracey said. "And now we have clinical trials showing that the human response is what's predicted by the lab experiments. Many scientific thresholds have been crossed in the clinic and the lab. We're literally at the point of regulatory steps and stages, and then marketing and distribution before this idea takes off."<br></p>The future of bioelectronic medicine
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTYxMDYxMy9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYzNjQwOTExNH0.uBY1TnEs_kv9Dal7zmA_i9L7T0wnIuf9gGtdRXcNNxo/img.jpg?width=980" id="8b5b2" class="rm-shortcode" data-rm-shortcode-id="c005e615e5f23c2817483862354d2cc4" data-rm-shortcode-name="rebelmouse-image" data-width="2000" data-height="1125" />Vagus nerve stimulation can already treat Crohn's disease and other inflammatory diseases. In the future, it may also be used to treat cancer, diabetes, and depression.
Credit: Adobe Stock via Maridav
<p>Vagus nerve stimulation is currently awaiting approval by the US Food and Drug Administration, but so far, it's proven safe and effective in clinical trials on humans. Dr. Tracey said vagus nerve stimulation could become a common treatment for a wide range of diseases, including cancer, Alzheimer's, diabetes, hypertension, shock, depression and diabetes.</p><p>"To the extent that inflammation is the problem in the disease, then stopping inflammation or suppressing the inflammation with vagus nerve stimulation or bioelectronic approaches will be beneficial and therapeutic," he said.</p><p>Receiving vagus nerve stimulation would require having an electronic device, about the size of lima bean, surgically implanted in your neck during a 30-minute procedure. A couple of weeks later, you'd visit, say, your rheumatologist, who would activate the device and determine the right dosage. The stimulation would take a few minutes each day, and it'd likely be unnoticeable.</p><p>But the most revolutionary aspect of bioelectronic medicine, according to Dr. Tracey, is that approaches like vagus nerve stimulation wouldn't come with harmful and potentially deadly side effects, as many pharmaceutical drugs currently do.</p><p>"A device on a nerve is not going to have systemic side effects on the body like taking a steroid does," Dr. Tracey said. "It's a powerful concept that, frankly, scientists are quite accepting of—it's actually quite amazing. But the idea of adopting this into practice is going to take another 10 or 20 years, because it's hard for physicians, who've spent their lives writing prescriptions for pills or injections, that a computer chip can replace the drug."</p><p>But patients could also play a role in advancing bioelectronic medicine.</p><p>"There's a huge demand in this patient cohort for something better than they're taking now," Dr. Tracey said. "Patients don't want to take a drug with a black-box warning, costs $100,000 a year and works half the time."</p><p>Michael Dowling, president and CEO of Northwell Health, elaborated:</p><p>"Why would patients pursue a drug regimen when they could opt for a few electronic pulses? Is it possible that treatments like this, pulses through electronic devices, could replace some drugs in the coming years as preferred treatments? Tracey believes it is, and that is perhaps why the pharmaceutical industry closely follows his work."</p><p>Over the long term, bioelectronic approaches are unlikely to completely replace pharmaceutical drugs, but they could replace many, or at least be used as supplemental treatments.</p><p>Dr. Tracey is optimistic about the future of the field.</p><p>"It's going to spawn a huge new industry that will rival the pharmaceutical industry in the next 50 years," he said. "This is no longer just a startup industry. [...] It's going to be very interesting to see the explosive growth that's going to occur."</p>Just how cold was the Ice Age? New study finds the temperature
Researchers figure out the average temperatures of the last ice age on Earth.
Icebergs.
- A new study analyzes fossil data to find the average temperatures during the last Ice Age.
- This period of time, about 20,000 years ago, had the average temperature of about 46 degrees Fahrenheit (7.8 C).
- The study has implications for understanding climate change.
Surface air temperatures during the last ice age.
Credit: Jessica Tierney, University of Arizona
Best. Science. Fiction. Show. Ever.
"The Expanse" is the best vision I've ever seen of a space-faring future that may be just a few generations away.
- Want three reasons why that headline is justified? Characters and acting, universe building, and science.
- For those who don't know, "The Expanse" is a series that's run on SyFy and Amazon Prime set about 200 years in the future in a mostly settled solar system with three waring factions: Earth, Mars, and Belters.
- No other show I know of manages to use real science so adeptly in the service of its story and its grand universe building.
Credit: "The Expanse" / Syfy
<p>Now, I get it if you don't agree with me. I love "Star Trek" and I thought "Battlestar Galactica" (the new one) was amazing and I do adore "The Mandalorian". They are all fun and important and worth watching and thinking about. And maybe you love them more than anything else. But when you sum up the acting, the universe building, and the use of real science where it matters, I think nothing can beat "The Expanse". And with a <a href="https://www.rottentomatoes.com/tv/the_expanse" target="_blank">Rotten Tomato</a> average rating of 93%, I'm clearly not the only one who feels this way.</p><p>Best.</p><p>Show.</p><p>Ever. </p>How exercise changes your brain biology and protects your mental health
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Here's a 10-step plan to save our oceans
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