Tuesday, March 28, 2017

Brushed by Showers Tonight - Minnesota Getting Off Easy Compared to Much of USA

65 F. maximum temperature yesterday in the Twin Cities.
48 F. average MSP metro high on March 28.
59 F. high on March 28, 2016.

March 29, 1986: Record warmth occurs with July-like temperatures. A monthly record high of 83 occurs at the Twin Cities.



Surprising Statistics on Severe Weather Risk

"There are three kinds of lies: lies, damned lies and statistics" Mark Twain said. He may have been overly optimistic. Statistics help when gauging relative risk. For example, you're almost 7 times more likely to drown in a bathtub than be struck by lightning.

NOAA statistics since 1986 show you're almost twice as likely to die from complications of extreme heat than tornadoes in the USA. River and flash flooding has claimed almost twice as many U.S. lives as hurricanes.

Tornadoes, hurricanes and blizzards get the air time, the local and national media attention, but flooding and extreme heat takes more lives across America. Vaguely interesting; hopefully the subject of inspired small talk at your next book club.

Meteorologists are at a rare and welcome loss for words: no drama for Minnesota anytime soon; the atmosphere too stable and dry for severe storm outbreaks. A lack of snow means a minimal river flood risk this year. Showers brush southern counties by tonight. Dry weather prevails Thursday PM into Sunday; highs in the 50s into early next week.

Keep a heavy jacket handy. A few more chilly relapses are all but inevitable.
Graphic credit above: NOAA.
Another Tornado Record's In Sight as Thunderstorms Boom. The most active tornado season in 5-6 years? Probably. Here's an excerpt from The Washington Post: "...The atmospheric moisture across the southern U.S. in January was more typical of April, Marsh said. A confirmed tornado touched down in central Massachusetts in February, a first, while there was still snow on the ground. The peak of tornado season varies across the country. Activity is concentrated in the Southeast early in the year, drifting into the Great Plains’ “Tornado Alley” in May and June before heading into the Northeast by early summer. The U.S. has more tornadoes than any other country, according to a report by Lloyd’s of London. The nation averages about 1,200 tornadoes a year, with the storms killing as many as 60 people and injuring 1,500, Lloyd’s said. Tornado “outbreaks,” or storm systems that spin out multiple funnels in a limited time and area, are becoming more frequent in the U.S., according to study published in the journal Science in December. Still, the trend isn’t consistent from what some models predicted would result from global warming, the study found..."
3 Storm Chasers Die in Texas Car Crash. ABC News has the details of this tragic story.
6 Life-Threatening Tornado Myths Debunked. Here's an excerpt from MSN.com: "...Another myth that could prove deadly is that seeking shelter under an overpass is safe. Experts warn that an overpass is not a safe shelter if a tornado is approaching. "Winds will actually funnel under the bridge and accelerate, which can cause the car to be pulled out," Warren said. Debris is another concern as the tornado can slam cars and other objects underneath bridges. If you happen to be caught on the highway and cannot get out of the path of a tornado, Warren said, seeking shelter in a ditch or remaining in your car is safer than being under an overpass..."
Maps Impersonating Spring. ECMWF guidance shows 50s into next week; even 60s the weekend after next as a flow from the Gulf of Mexico strengthens. It looks too cool, dry and stable for any significant severe storm outbreaks into the middle of next week. MSP numbers: WeatherBell.

No Rest For the Weather-Weary. The same storm that spawned tornadoes and baseball-size hail across Texas and Oklahoma Tuesday will spread a pinwheel of rain across the Upper Midest and Ohio Valley, eventually pushing heavy wet snow into much of New England by Friday and Saturday. Meanwhile the rains just don't want to quit for the Pacific Northwest with more snow for the intermountain west in the coming days. 12 KM NAM Future Radar product: NOAA and Tropicaltidbits.com.


A Bad Meteorological April Fool's Day Joke? We'll see how this unfolds, but models bring a (very) plowable snowfall across central Michigan into upstate New York and much of interior New England. A foot from Albany to Worcester? We'll see, but travel north and west of New York City and Boston may be extremely tricky Friday night into Saturday. 12 KM NAM guidance above.
Mid-April: Mild and Thundery Central USA? 500 mb winds may cut off roughly 2 weeks out, if the GFS verifies, meaning a sloppy, potentially thundery weather holding pattern for the Plains and Midwest with mild sunshine for much off the eastern USA and drying for California. More rain for the Pacific Northwest? Good grief.

Forecasts For This Past Winter Were Mostly Awful. Blame the Fickle Pacific Ocean. We were supposed to slide into a La Nina cooling phase, but in recent months the pattern has resembled a severe El Nino pattern with wave after wave of Pacific moisture slamming the west coast. Here's an excerpt of an explainer from Jason Samenow at Capital Weather Gang: "Predicting the weather for winter many weeks before it begins is hard. If any season proved there is a long ways to go in perfecting such long-term outlooks, this winter was it. I am not aware of any outlet in the government, media or private sector which nailed the 2016-17 winter outlook. In fact, some forecasts predicted the opposite of what happened. The National Weather Service and The Weather Company probably had the best outlooks of those I reviewed although they were far from perfect. Across all of the various outlooks, the forecast errors were linked to a Pacific Ocean that did not behave as expected. Storms traveling across it were supposed to mostly pass to California’s north. Instead, time and time again they hit the Golden State head-on, unloading historic amounts of rain and snow, while flooding much of the rest of the nation with abnormally warm air..."

Photo credit: "Chairlift buried in snow, Feb. 22, 2017 at Squaw Valley Alpine Meadows, Calif." (Squaw Valley Alpine Meadows Resort)
Tornadoes Striking at Record Pace in U.S. So Far This Year. It's going to be an extra-long severe and tornado season, at the rate we're going. Here's an excerpt from MLive.com: "...The storm track in January, February and March has taken strong storms across the U.S. These strong storms are tracking farther north than usual for this time of year, resulting in much warmer than normal temperatures being pulled northward into the Midwest. So the storm track has been more typical of April or May, even in the middle of winter. As a result, severe weather amounts have been more typical of April or May..."
Leigh Orf Creates Super-Storms From the Comfort of His Desk. Supercomputer simulations of super-cell thunderstorms, the rotating monsters that often go on to spin up tornadoes, is improving rapidly as speeds increase and costs continue to come down. Here's an excerpt of an interview at madison.com: "...I have to say this is just one simulation, but there are two main takeaways that I'll give you. Before the tornado forms, there are a whole bunch of mini-tornadoes. They're not actually called tornadoes, they're called mesocyclones. They're little spinning whorls of air that are maybe 100 yards in diameter. They're in the simulation, but you can't see them in the atmosphere — the air is spinning, but it's not kicking up debris and there's no cloud...they're kind of scooting into where a tornado would form. The second thing we've noticed, we gave a name: we call it a streamwise vorticity current. In a storm, there's cold air that's formed by the storm itself...the storm is producing this cold pool of air. One of the things my simulation is suggesting is that the tornado is made up of air from that cold pool. But there's a certain feature we've identified that's sort of hard to explain in words — it's a helically flowing horizontal thing of air, that kind of goes up and becomes tilted into the supercell..."
Cyclone Debbie: Deadly Cyclone Batters Australia. BBC News has an update: "A powerful cyclone has pummelled the north-east Australian coast, causing major damage, torrential rain and power cuts to tens of thousands of homes. Cyclone Debbie made landfall between Bowen and Airlie Beach in Queensland as a category four storm, whipping gusts of up to 263km/h (163mph). It is moving inland as a category two storm but could cause damage for hours yet. Prime Minister Malcolm Turnbull said he was aware of one death so far. Activating a disaster response plan, he stressed the picture could develop when emergency crews were able to assess the damage..."
WMO "Retires" Two Hurricane Names. Here's an excerpt from a NOAA press release: "You’ve heard the last of Matthew and Otto – at least as Atlantic storm names. These two storms ravaged the Caribbean so much last year their names have been retired by the World Meteorological Organization’s Region IV Hurricane Committee, of which NOAA's National Hurricane Center is a member. Matthew and Otto are the 81st and 82nd names to be removed from the Atlantic list. Storm names are retired if they were so deadly or destructive that the future use of the name would be insensitive. Matthew became a category 5 storm on the Saffir-Simpson scale on the night of Sept. 30, over the central Caribbean Sea at the lowest latitude ever recorded in the Atlantic Basin..."
Interested in Becoming a NOAA Weather Observer? They're looking for volunteers to help with observations, click here to learn more about CoCoRaHS.
A Century-Old Arctic Shipwreck Could Help us Predict Extreme Weather. FiveThirtyEight has a fascinating tale: "...Today, the Jeannette’s recovered logbooks tell incredible stories about life, death, Arctic temperatures, fear and boredom. The records, which originally existed only in federal archives, are now available to anyone who wants to read them on a website called Old Weather. Old Weather is a gathering place for more than 4,500 citizen-sleuths who are helping climate scientists map our planet’s ancient weather patterns, for free, one logbook at a time. These volunteers read and transcribe notes from sailors, hoping to map the mostly unknown history of our planet’s weather patterns. According to Kevin Wood, an Old Weather co-founder, examining the past in this way is key to understanding the earth’s future..."
How Much Does a Cloud Weigh? Check the math, but the calculations described at Mental Floss seem to pan out: "...Next, figure out how big the cloud is. By measuring a cloud’s shadow when the sun is directly above it, you can get an idea of its width. LeMone does this by watching her odometer as she drives under a cloud. A typical cumulus, she says, is about a kilometer across, and usually roughly cubical—so a kilometer long and a kilometer tall, too. This gives you a cloud that’s one billion cubic meters in volume. Do the math with the density and volume to determine the total water content of the cloud. In this case, it's 500,000,000 grams of water, or 1.1 million pounds. That’s a lot of weight to wrap your head around, so LeMone suggests putting it in more familiar terms, like elephants. That cloud weighs about as much as 100 elephants. If you’re a Democrat and you’re feeling partisan, she says, you could substitute 2500 donkeys. If you care more for dinosaurs than politics, you could also say the cloud weighs about as much as 33 apatosauruses..."

Great American Eclipse. Check out this amazing web site for everything you need to know for the total solar eclipse coming up on August 21: "On August 21, 2017, millions of people across the United States will see nature's most wondrous spectacle — a total eclipse of the Sun. It is a scene of unimaginable beauty; the Moon completely blocks the Sun, daytime becomes a deep twilight, and the Sun’s corona shimmers in the darkened sky. This is your guide to understand, prepare for, and view this rare celestial event. A total solar eclipse is unlike anything you've seen in your life. As totality approaches, you will see the astonishing sight of day turning to night and the Sun's corona blazing in the sky. This is truly a great American eclipse because totality will sweep the nation from the Pacific to the Atlantic. Nearly everyone in the US can reach this total solar eclipse within one day's drive.  An eclipse is a cosmic billiard shot — the Sun, Moon, and Earth line up to reveal the Sun's atmosphere, it's corona. Eclipses on Earth occur only because of an amazing celestial coincidence..."
"Jet Stream" on the Sun May Help to Provide Better Solar Flare Forecasts. Here's an excerpt of a fascinating story at Cosmos: "Scientists studying 360-degree images of the sun have discovered that deep in its atmosphere, its magnetic field makes looping meanders intriguingly analogous to the earth’s jet stream. Technically known as Rossby waves, these meanders were traced by observing their effect on coronal brightpoints — small bright features that dot the sun. Their movements can be used to track motions deeper in the solar atmosphere. They are not particularly fast, especially when measured against the huge scale of the sun itself. “We get speeds of three metres per second,” says Scott McIntosh, a solar physicist from the National Centre for Atmospheric Research in Boulder, Colorado, USA. “Slow, but measurable...”
More Than Any Other Industry, Science Makes America Great. I couldn't agree more. Here's the intro of a must-read story at GOOD: "There is perhaps no community that deserves more credit for “making America great” than our scientists, whose innovations have contributed trillions of dollars to the U.S. economy, launched the world’s most advanced military force, and saved millions of lives. In case you need it, here’s a refresher on the greatest hits: Benjamin Franklin deepened our understanding of electricity; Thomas Jefferson’s weapons technology helped us win the Revolutionary War; then there was Eli Whitney’s cotton gin; Robert Fulton’s steamboat; Thomas Edison’s light bulb, phonograph, and literally a thousand other patents; the Wright Brothers’ airplane; Henry Ford’s Model T; and—for better or worse—the massive team of scientists on the Manhattan Project team, responsible for the atom bomb and nuclear energy. Oh, yeah, and we landed on the moon. Skip ahead to the internet, which was developed largely by American scientists and engineers in collaboration with the Department of Defense..."

Photo credit: "There's a reason we put a scientist on our $100 bill."
California is Shattering Solar Records. This Bill Could Take Renewable Energy to the Next Level. The Desert Sun reports: "A month ago, California broke its all-time solar record, with nearly 8,800 megawatts of solar power flooding the state's main electric grid on a Friday afternoon. The record stood until the following Wednesday, when more than 9,000 megawatts of solar powered the Golden State, according to the California Independent System Operator, which runs the grid. That record didn't even last 24 hours. With the costs of solar continuing to fall, and wind still one of the cheapest sources of new electricity around, California should have no problem hitting its 50 percent clean energy target by 2030..."

File photo: Zuma Press.

Clean Energy Employs More People Than Fossil Fuels in Nearly Every U.S. State. Here's a clip from ThinkProgress: "Nationally, clean energy jobs outnumber fossil fuel jobs by more than 2.5 to 1, according to a new Sierra Club analysis of Department of Energy jobs data. And when it comes to coal and gas — two sectors President Donald Trump has promised to bolster through his upcoming executive order on energy regulation — clean energy jobs outnumber jobs dealing with those two fossil fuels by 5 to 1. “Right now, clean energy jobs already overwhelm dirty fuels in nearly every state across America, and that growth is only going to continue as clean energy keeps getting more affordable and accessible by the day,” Sierra Club executive director Michael Brune said in a statement..."

Photo credit: AP Photo/Ross D. Franklin.
Madison Commits to 100% Clean, Renewable Energy. Midwest Energy News has the story: "Madison, Wisconsin committed to getting 100 percent of its energy from clean, renewable sources in a resolution passed unanimously by the City Council on Tuesday. It became the 24th city to make such a promise, according to a tally by the Sierra Club, which has a “Ready for 100” nationwide campaign. Madison’s resolution sets a high bar in a state that gets most of its electricity from coal and where, as in most places, natural gas is almost exclusively used for heating during harsh winters. Madison’s resolution calls for the entire city to get all of its power from clean renewable sources, starting with city operations..."
Ad Trust Rises as News Trust Sinks. A significant percentage of consumers believe advertisements are now more credible and believable than news? I have some spam I'd like them to examine for me. Here's an excerpt from Axios: "A new survey finds that 61% of people trust the advertising they see, an 11% jump from March 2014, according to eMarketer. In addition, 72% of respondents also said the ads are "honest," a 16% increase over the past two years. Other studies have indicated that ad trustworthiness depends on the medium. Some studies show people are less likely to trust digital ads vs. traditional print or television ads. Why it matters: The most recent Gallup poll on trust in media shows that 68% of Americans don't trust the news - the lowest rate ever measured..."
Silicon Valley's Quest to Live Forever. Playing God? What can possibly go wrong. Here's an excerpt from a New Yorker article: "...For us, aging is the creeping and then catastrophic dysfunction of everything, all at once. Our mitochondria sputter, our endocrine system sags, our DNA snaps. Our sight and hearing and strength diminish, our arteries clog, our brains fog, and we falter, seize, and fail. Every research breakthrough, every announcement of a master key that we can turn to reverse all that, has been followed by setbacks and confusion. A few years ago, there was great excitement about telomeres, Liz Blackburn’s specialty—DNA buffers that protect the ends of chromosomes just as plastic tips protect the ends of shoelaces. As we age, our telomeres become shorter, and, when these shields go, cells stop dividing. (As Blackburn said, “It puts cells into a terribly alarmed state!”) If we could extend the telomeres, the thinking went, we might reverse aging. But it turns out that animals with long telomeres, such as lab mice, don’t necessarily have long lives—and that telomerase, the enzyme that promotes telomere growth, is also activated in the vast majority of cancer cells. The more we know about the body, the more we realize how little we know..."

Photo credit: "Researchers store vials of aging cells in liquid nitrogen for use in future experiments. If work progresses slowly, some also plan to freeze themselves, with instructions to reawaken them once science has finished paving the way to immortality." Photograph by Grant Cornett for The New Yorker.
Could You Give Up TV For a Year? Not sure I could, but I salute the people who have. Here's an intriguing story at The Washington Post: "...Americans are obsessed with television, spending an average of five hours a day pointing ourselves at it even as we complain we’re busier than ever. It rules our lives, whether we admit it or not. A friend of mine claims to not watch much TV, but whenever I visit her — morning, noon or night — it’s on. After my husband admitted we hadn’t watched any while on vacation, a family member was floored: “A whole week without TV?” And when I showed off my new house, visitors were most excited about the cable outlet on the back porch; now I can even point my outdoor furniture at a TV. But for all the time we spend with it, TV doesn’t repay us very nicely. People who watch more television are generally unhappier, heavier and worse sleepers, and have a higher risk of death over a defined length of time. Studies have found links between children and teenagers who watch a lot of TV and worse attention spans, lower grades and structural differences in brain regions associated with intelligence..."
Why You Should Be Walking 7 Miles a Day - At Least. Does driving 7 miles a day count? Here's a snippet from Esquire: "...But walking any amount lessened the risk, putting the mail carriers at an advantage. Mail carriers who walked more than three hours a day had no heightened risk for heart disease at all—their BMIs, metabolisms, cholesterol levels, and blood sugar levels were normal. So, according to this (small, limited) study, 15,000 steps keeps people healthy. For those curious, 15,000 steps is equivalent to about seven miles of walking. Easy. People can get 15,000 steps a day "by walking briskly for two hours at about a four-mile-per-hour pace," lead researcher Dr. William Tigbe told The Times. (An average walking pace is three miles per hour.) Another totally realistic suggestion was "a 30-minute walk before work, another at lunch, and multiple 10-minute bouts throughout the day..."
Frogpocalypse Now. What is the deal with cane toads in south Florida? Feeling better about Minnesota's mosquitoes after reading a story at Outside Online: "...Cane toads have these things going for them: they are bigger than other toads (the biggest cane toad on record weighed 5 pounds 13 ounces, almost as much as a Kalashnikov rifle); they lay huge numbers of eggs, perhaps 30,000 in a breeding season (the southern toad, a species they appear to be displacing in Florida, lays about 4,000); and they are highly poisonous (their venom, carried in glands in their shoulders, kills animals, and could kill a person, though so far no Floridian is known to have been poisoned by it). On top of all that, they can eat almost anything. All amphibians are carnivorous, but cane toads stretch the description. Besides insects, they vacuum up snakes, worms, grubs, snails, mice, small rats, bats, young birds, other amphibians (sometimes their own young), pet food, and garbage. They differ from most other frog species in that they can identify food that is not moving..."

Image credit: Simón Prades.

TODAY: More clouds stream in, showers late. Winds: SE 8-13. High: 54

WEDNESDAY NIGHT: Scattered showers, mainly southern Minnesota. Low: 38

THURSDAY: Damp start, then slow clearing. Winds: E 8-13. High: near 50

FRIDAY: Partly sunny, mostly springy. Winds: NE 5-10. Wake-up: 36. High: 55

SATURDAY: Mix of clouds and sun, pleasant. Winds: SW 5-10. Wake-up: 41. High: 58

SUNDAY: Sunny spells, liking April so far. Winds: S 5-10. Wake-up: 42. High: 59

MONDAY: Unsettled with showery rains. Winds: SE 7-12. Wake-up: 41. High: 54

TUESDAY: Rain lingers, cool and soggy. Winds: SE 10-15. Wake-up: 45. High: 52

Climate Stories...

Trump Moves Decisively to Wipe Out Obama's Climate Change Record. Here's a snippet from The Washington Post: "President Trump will take the most significant step yet in obliterating his predecessor’s environmental record Tuesday, instructing federal regulators to rewrite key rules curbing U.S. carbon emissions. The sweeping executive order also seeks to lift a moratorium on federal coal leasing and remove the requirement that federal officials consider the impact of climate change when making decisions. The order sends an unmistakable signal that just as President Barack Obama sought to weave climate considerations into every aspect of the federal government, Trump is hoping to rip that approach out by its roots. “This policy is in keeping with President Trump’s desire to make the United States energy independent,” said a senior administration official who briefed reporters on the directive Monday evening and asked for anonymity to speak in advance of the announcement..."
Exxon Urges Trump to Keep U.S. in Paris Climate Accord. Here's an excerpt at Financial Times: "ExxonMobil, the largest American oil group, has written to the Trump administration urging it to keep the US in the Paris climate accord agreed at the end of 2015. In a letter to President Donald Trump’s special assistant for international energy and the environment, Exxon argues that the Paris accord is “an effective framework for addressing the risks of climate change”. The letter was sent last week, but has emerged as Mr Trump is preparing to announce executive orders beginning a rollback several of Barack Obama’s climate policies, while leaving the question of Paris open. Trump administration officials have said a decision on participation in Paris is still “under discussion”, and have been soliciting views from US energy companies..."
Northwest Governors Vow to Resist Plans to Gut Climate Change Rules. Northwest Public Radio has more information: "The Trump Administration is expected to announce plans to reverse drafts of Obama-era climate change policies this week. Governors and mayors along the West Coast have stated their opposition to the move. Oregon Governor Kate Brown and Washington Governor Jay Inslee declared Saturday their intention to forge ahead with regional climate change efforts. Speaking at the Washington State Department of Commerce in Seattle, Inslee and Brown said they wouldn’t allow the White House to derail climate change policies and programs the region has put in place. Inslee said he assured a United Nations climate conference in New York Thursday that the West Coast states would not reverse course. "The West Coast is going to move forward to beat climate change," Inslee said..."

Image credit: "Oregon Governor Kate Brown and Washington Governor Jay Inslee said they plan to "fight back" against President Trump's environmental rollbacks." KING5 TV, Seattle.
A Building Boom and Climate Change Create an Even Hotter, Drier Phoenix. The Los Angeles Times reports: "This sprawling metropolis morphed in a matter of decades from a scorching desert outpost into one of the largest cities in the nation. Today, Phoenix is a horizon of asphalt, air conditioning and historic indifference to the pitfalls of putting 1.5 million people in a place that gets just 8 inches of rain a year and where the temperature routinely exceeds 100 degrees. Now, however, the city faces a reckoning. It is called climate change, and it is expected to further expose the glaring gap between how the city lives and what it can sustain. The future, scientists say, will be even hotter and drier, the monsoons more mercurial. Summertime highs could reach 130 degrees before the end of the century — think Death Valley, but with subdivisions..." (File photo: Greater Phoenix Chamber of Commerce).
Finding Common Ground on Climate Issues. Here's an excerpt of an Op-Ed at newsminer.com in Fairbanks, Alaska: "...An independent study of this type of revenue-neutral fee and dividend found that it would significantly reduce harmful carbon emissions while creating millions of jobs and preventing thousands of premature deaths by improving local air quality. Every American would get an equal share of revenues from the carbon fee, and a large majority of Americans would actually come out ahead, with dividends larger than increased fees. It would be hard to find a more effective, efficient and fair way to start mitigating climate pollution at the national level. The political situation has made it hard for Republicans to speak up on climate change. But climate change has not always been a partisan issue, and there’s no reason it should be. Responsible use and protection of natural resources is important to many conservatives. And it would be foolish to think only Democrats want a healthy environment for their children and grandchildren..." (File photo: Media Matters).

When Is It Time to Retreat from Climate Change? America already has its first climate refugees, due to rising seas, land subsidence and coastal beach erosion in Alaska and Louisiana. This is a question that will be asked with greater frequency and urgency in the years to come. Here's an excerpt at The New Yorker: "...In a paper published today in the journal Nature Climate Change, a trio of Stanford researchers examined twenty-seven recent cases of managed retreat affecting twenty-two countries and 1.3 million people. They found that, regardless of a country’s wealth and level of development, relocations are most likely to happen when a government and its citizens are in accord. In the early two-thousands, for instance, the Dutch farming community of De Noordwaard was “de-poldered”; its seventy-five households were moved, its protective dikes were lowered, and its land was allowed to flood. Residents who initially opposed the retreat came around after repeated inundations, and the government’s initiative helped not only them but also many thousands of others downstream. Likewise, after the Australian state of Queensland suffered a series of catastrophic floods in late 2010 and early 2011, more than two hundred and fifty people in the Lockyer Valley chose to leave, first with local government support and later with assistance from the state and national governments..."

Photo credit: "An aerial view of Isle de Jean Charles, in southern Louisiana." Photograph by William Widmer, REDUX. 

CO2 Spike. NASA has more details on carbon dioxide measurement and trends.
Climate Change-Fueled Jet Stream Linked to Brutal Floods and Heat Waves, Says Study. The jet stream is becoming wavier over time, more sprawling, full latitude dips and bulges that tend to amplify floods, heat and drought, according to new research highlighted at InsideClimate News: "...The Rossby waves shape day-to-day and seasonal weather, said Rutgers University climate researcher Jennifer Francis, who was not involved in the study but has done related research on changes in hemispheric wind patterns. The northward loops carry warm air up from the tropics and help form high pressure systems, associated with warm and dry weather. The southward dips pull cold Arctic air down, generating stormy low pressure areas, she explained. The study found that as greenhouse gases have increased in the atmosphere, those waves have lingered longer over particular regions. "Anything that makes those waves more persistent means the weather is going to be more persistent too, and summer extreme events are associated with these persistent patterns," Francis said. The 2010 summer heatwave over Siberia and simultaneous widespread flooding in Pakistan was a classic example of such a "stuck" pattern, according to Francis. "What we're learning is there are multiple ways that global warming is going to affect weather systems in different regions and different seasons..."
Climate Change: Human Fingerprint Found on Global Extreme Weather. No, you're probably not imagining it - the extremes do, in fact, appear to be getting more extreme over time, especially rainfall, heat and drought. More perspective on the research highlighted in the previous article from The Guardian: "...The new work analysed a type of extreme weather event known to be caused by changes in “planetary waves” – such as California’s ongoing record drought, and recent heatwaves in the US and Russia, as well as severe floods in Pakistan in 2010. Planetary waves are a pattern of winds, of which the jet stream is a part, that encircle the northern hemisphere in lines that undulate from the tropics to the poles. Normally, the whole wave moves eastwards but, under certain temperature conditions, the wave can halt its movement. This leaves whole regions under the same weather for extended periods, which can turn hot spells into heatwaves and wet weather into floods. This type of extreme weather event is known to have increased in recent decades. But the new research used observations and climate models to show that the chances of the conditions needed to halt the planetary waves occurring are significantly more likely as a result of global warming..." (Image credit: NASA).

The new research on planetary waves and climate change referenced above is here.

20 Common Myths That Climate Scientists Often Hear. Dr. Marshall Shepherd has done a public service by organizing the 20 biggest (whoppers). Here's an excerpt of a recent post at Forbes:

1. The climate always changes naturally, and we always had extreme weather. This is an accurate statement but misses the point that natural cycles can be altered by anthropogenic processes (Natural growing grass+fertilizer and Major League Baseball-home runs in the steroid era). Natural processes have always and will continue to affect climate. We just have to figure out how this relatively new anthropogenic "ingredient" is modifying the recipe.

2. Ok, the climate is changing but how do we know humans are contributing? There are a couple of good public-focused resources to answer this. One, from Bloomberg, provides a visual graphic to explain relative contributors to climate warming, and the other, from The Economist, explains it with text. For science background, the Intergovernmental Panel on Climate Change (IPCC) report is a good source....

Image credit: NASA.
One of the Most Troubling Ideas About Climate Change Just Found New Evidence in its Favor. To think that rapid changes in the arctic won't have any impact on weather at our latitude is the height of wishful thinking. Chris Mooney reports at The Washington Post; here's an excerpt: "...But when the Arctic warms up faster than the equator does — which is part of the fundamental definition of global warming, and which is already happening — the jet stream’s flow can become weakened and elongated. That’s when you can get the resultant weather extremes. “It’s sort of like if you confine an electromagnetic wave to a coaxial cable, then you’re not losing energy, it’s being tightly contained in that cable and sent to your television,” said Mann. “These waves aren’t losing energy, so they grow and get larger and get stuck in place as well.” What the new study is saying is that in summer, in particular, this can occur. Moreover, it finds that a particular temperature pattern is linked to that behavior — and this temperature pattern, featuring an extra warm Arctic, is becoming more frequent over time, based on both observations and also a review of the outputs of high powered climate change models that the researchers conducted. “We think that the signal has emerged from the noise over the last decade,” said Mann..."

Image credit: "This animation shows changes in the polar jet stream from June 1, 2015 to July 31, 2015. The jet stream is approximated by crosses. The northerly shift of the jet stream may be linked to a warming arctic, and record melt of the Greenland ice sheet in 2015." (Marco Tedesco/Lamont-Doherty Earth Observatory)

More Warm Spring Days. Not every day, but the trend is more warmth earlier in the warm season, according to Climate Central: "...Spring is getting warmer, on average, as the globe heats up from the increase in greenhouse gases in the atmosphere. As a result, the number of spring days with above-normal temperatures is increasing in many places in the U.S. In an unchanging climate, the number of days above normal and below normal should be relatively balanced and constant through the years. For meteorological spring, that number would be 46 out of the 92 days. In the majority of these cites, the number of days above normal has risen sharply. In some cases, there are more than 10 additional above-normal days than there were a few decades ago..."

What You Can Do About Climate Change. There are lots of things you can do, including voting for pro-science politicians running for local, state and national offices. An article at The New York Times argues that the most important thing you can do is drive a more fuel-efficient vehicle: "...The simple fact is that American drivers are a significant contributor to greenhouse gas pollution, so having a vehicle fleet that burns less fuel can have an outsize impact on total emissions. Though the United States has just 4 percent of the world's population, it is responsible for 14 percent of man-made greenhouse gases that end up in the atmosphere. Transportation accounts for 27 percent of those emissions. And 60 percent result from driving personal vehicles..."
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