Courtesy JoeThis past July I was Up North at the family cabin in northern Minnesota and saw this amazing rainbow. It by far and away was the brightest rainbow I had ever seen. And, in addition, there was this second, fainter rainbow, to the right (seen in this picture).
I was very curious about this second rainbow and wanted to see how that was possible. And where did I learn my answer? Right here on Science Buzz thanks to mdr! Here's the scoop from his blog on this topic from a few years ago:
Basically, rainbows are the result of sunlight being once reflected and twice refracted by raindrops. Certain conditions are required. First and foremost, the viewer needs to be located between the sun and rain clouds. A ray of sunlight enters an individual drop of water and is refracted (bent) as it enters, then reflected from the back of the drop, and refracted again as it exits the drop. The refractions cause the white sunlight to divide into separate colors. Each color refracts in slightly different amounts, red the least, and violet the most. A particular raindrop will reflect red light because it is positioned at just the right angle from your eye (42°). This is known as the “rainbow ray”. Another droplet located at a slightly different position will reflect blue light to your eye. Now multiply this by the innumerable suspended water droplets that make up a rain cloud, and you have a rainbow.
The main colors in a primary rainbow will have red at the top followed by orange, yellow, green, blue, indigo, and violet. An easy way to remember the order is to note that the first letter of each color spells out the name ROY G. BIV.
The rainbow I witnessed had a second, fainter rainbow just above the first. This is the result of some light being reflected twice, and at a higher angle. The colors in a secondary arc are reversed with red on the bottom and violet on top.
Courtesy Paige Shoemaker
Next time you look at the clouds, shake your fist and yell at those jerks for making our lives difficult. You might look crazy, but somebody needs to tell those fools.
While it's relatively easy to model temperature changes over the last century thanks to detailed records, clouds are more tricky to understand because we don't have a similar history of cloud observations, and also because they are ornery. So in order to understand how clouds work, scientists are building a body of evidence to model cloud behavior and help show how clouds will impact our weather as well as our climate in the future. I believe they also plan to show those clouds who is the boss of them.
Like a child running loose in a toy store, hurricanes have always been difficult to predict because they can unexpectedly change direction. This confounds plans for evacuation, leading some people to leave areas that are never hit, leading others to stay put and potentially face nasty weather because they don't trust the meteorologist, and leading meteorologists to keep Advil in business. But since the 90s, our ability to predict where hurricanes will make landfall has become twice as accurate. This new prescience is due to the development and use of more accurate models of how clouds work, which is in turn due to better understanding of cloud dynamics and faster computers. How about that, punk clouds?
Intensity, however, remains elusive to model. (Shh, don't let them know we have a weakness!)
"While we pride ourselves that the track forecast is getting better and better, we remain humbled by the uncertainties of the science we don't yet understand," Schott said. "This is not an algebra question where there's only one right answer."
Despite being a "forecasting nightmare," Earl ended up hitting about where it was predicted to go. This means that the right people have been evacuated to avoid injury and fatality. That's right, stick your tail between your legs, Earl.
Connecting to climate
Short-term events such as hurricanes and other storms are difficult to predict, but climate change is a whole other world of uncertainty--again, thanks to those uncouth clouds. Climate scientists are developing new tools, such as satellite technologies that show how much light different cloud types reflect and models that demonstrate localized cloud processes. These approaches look specifically at certain groups of clouds and their patterns of change to add detail to older, larger models that look at climate over larger scales.
Courtesy Nic McPhee
The problem with the older models is that they have a low resolution that doesn't accurately represent clouds because the clouds are smaller than they can show. Think of it like Google maps--at the beginning, you're looking at the entire planet, or a whole continent--this is similar to older, low-res climate models. The new models are like zooming in on a city--you can see bus stops, restaurants, and highways. But you have to zoom out to see how these small pieces relate to the larger surroundings. In a similar way, the new high-res models are helping to inform older models--this type of work is called multiscale modeling.
Researchers at the Center for Multiscale Modeling of Atmospheric Processes (CMMAP) are developing this exact type of model. You can read about their advances here. This work is important because it brings insight into questions about whether clouds will reflect or trap more sunlight, which can have a big impact on the rate of global warming. It also helps us understand whether geoengineering projects that alter clouds will really have the intended effect. Plus it's just one more way we can pwn clouds.
Courtesy wvs (Sam Javanrouh)In a paper delivered at the 240th National Meeting of the American Chemical Society in Boston, a researcher envisioned a time in the not-too-distant future when houses and buildings outfitted with the proper equipment would be able gather electric energy stored in humidity in the atmosphere that could be used to fill a community’s electrical needs.
The concept isn’t new; electrical wunderkind Nikola Tesla had a similar idea more than a century ago.
Science has long sought the answer to how electricity builds up and discharges in the atmosphere, and whether the moisture in the atmosphere could even hold an electrical charge. But Fernando Galembeck, a professor at Brazil’s University of Campinas, claims he and his research team have successfully shown that it can, and by using special metal conduits to collect that electricity, it could allow homeowners and building managers to gather and store the electricity as an alternative energy source.
”Just as solar energy could free some households from paying electric bills, this promising new energy source could have a similar effect,” Galembeck said. He terms the new method “hygroelectricity” which means “humidity electricity”. Galembeck's research could also add to our understanding of how thunderstorms form.
In their laboratory experiments, Galembeck’s research team created a simulated atmosphere densely saturated with water (humidity), which they seeded with silica and aluminum phosphate, two chemical compounds commonly found in air. As water droplets formed around the tiny, airborne chemical substances, the researchers noticed the silica took on a negative charge while the aluminum phosphate droplets held a positive charge. The charged water vapor readily condenses upon contact with surfaces such as a cold can of soda or beer, and on the windows of air-conditioned buildings or vehicles. In the process, energy is transferred onto the contact surface.
“This was clear evidence that water in the atmosphere can accumulate electrical charges and transfer them to other materials it comes in contact with,” Galembeck said.
Just as solar panels convert energy from sunlight into a usable power source, the researchers think water vapor in the atmosphere could someday be harvested for its hygroelectric energy. The rooftops of buildings in regions of high humidity and thunderstorm activity could someday be fitted with special hygroelectric panels that would absorb the charges built up in the humid atmosphere and funnel the energy to where it can be utilized, and at the same time reduce the risk of lightning forming and discharging. The technology would be best suited to regions of high humidity, such as the tropics or the eastern and southeastern U.S.
Thunderstorm over Lake Harriet in Minneapolis; Could this be a new source of energy for the Upper Midwest?
Courtesy Lori GeigWell, no, I won’t literally shout it into your brain. First of all, I’m writing this in the near past, and it’s difficult to shout in this medium anyhow. Also, even if we were right next to each other at the same time, I’d really be shouting into one of your ears, or possibly into your face. To shout into your brain, I’d need some sort of saw, or a hammer, and I’d definitely need your cooperation. (I’m just that kind of guy.) So the shouting thing is out.
But it’s really important that you understand the difference between weather and climate, or folks are going to take advantage of your confusion. They’ll do it with op-eds and obnoxious little bumper stickers instead of with a hammer, but it will still be unpleasant in the end.
So here’s the thing: weather and climate are not the same.
See, you may say to yourself, “I know the difference between weather and climate. I’m smrt!” And you may very well be smert, but there’s a decent chance that you still let weather fool you into thinking it’s climate. As this article in the NY Times points out, plenty of samart people still confuse the two concepts, or at least use one (weather) to make points about the other (climate).
Let’s be different. Let’s be truly smaret people, and get this cleared up once and for all. Weather is not the same thing as climate.
Weather is day-to-day, climate is year-to-year, or decade-to-decade, or century-to-century. Weather is immediate, and we feel it acutely, so it weighs on our minds. But it isn’t climate, which is so long-term that even very smar people tend to miss the point.
The East Coast had a frigid snowy winter, so global warming must be myth, right? But the Midwest and Russia have been having a hot hot summer, so we must be in the burning grip of global warming, right? No. If either is the case, a cold winter or a hot summer isn’t the evidence for it.
Back in the year 1991, there was a blizzard on Halloween. If was off the hooook! I was a jawa, or something, and I trick-or-treated my way through about two and a half feet of snow. Crazy, right? But does that crazy Halloween blizzard mean that October is a very snowy month in Minnesota? Of course not! Who would even think that?
What if we (Minnesotans) got a couple solid weeks of rain right now, at the tail end of summer? That would be a damp way to spend the Labor Day weekend. But would it mean that Minnesota is on its way to becoming a rainforest. No, no it wouldn’t. A rainy couple weeks, or even a whole rainy summer, is weather. Climate is weather (temperature, wind, humidity, atmospheric pressure, precipitation, etc) averaged out over years and years. I’m sorry if your birthday was ruined by a freak firestorm, but that doesn’t have a thing to do with climate, so stop making that demonstration sign with a picture of your cake melting.
Maybe it seems obvious, but we still tend to use weather as a substitute for climate even when we think we understand it. Consider the concept of “Global Warming’s Six Americas.” A report from Yale University has found that people can be placed into six groups regarding their feelings on climate change: alarmed, concerned, cautious, disengaged, doubtful, or dismissive.
People who fall into the extreme categories, the freaking-out “alarmed” and the denying “dismissive,” typically aren’t swayed by day-to-day weather—they might use it to further their own arguments, but they (rightly) don’t let it affect their perceptions of long-term climate behavior.
Everyone else, the various shades of undecided, however, is influenced by the local weather, often subconsciously.
Say what?! Clever people that we are, we still allow the wrong evidence to influence our opinions on huge, important issues?! We have to be smaearter than that! So whenever your jerky aunt or your shrill uncle are trying to tell you that the Christmas heat wave or the frosty July mornings are evidence for or against global warming, run the information through your own brain, and when your brain tells you that you need to consider years and years worth of information before you can make that call, you can tell them to shove it.
Of course climate is made up of weather—lots and lots and lots of weather—but, as an author of a report on the subject puts it, making generalizations about climate based on weather “is like asserting how the economy is doing by looking at the change in your pocket. It’s relevant, but not that relevant.”
I like to think of it another way, too. Like, in Home Alone, just because Kevin Mcallister’s family called him “such a disease,” and left him home alone that one time, it didn’t mean that they didn’t really love him. To actually switch to a climate of non-love, the Mcallisters would have to call Kevin a disease every day for years and years, and maybe even stop feeding him.
To say the climate is changing, or not changing, you have to look at the weather data over many years. So do that, instead of forming opinions on whatever is bugging you on a particular day. Don’t be a chump. Be smart.
As of Aug 20, Minnesota has had 123 tornadoes. Texas is number two with only 87. Minnesota has never been number one in tornadoes before.
Courtesy Mark RyanLast week, Lake Superior, which is bordered by Minnesota, Wisconsin, Michigan, and Ontario, Canada, recorded its highest average surface temperature ever, a balmy 68.3°F. People seeking relief from a very hot summer have been flocking to the shores and beaches and actually swimming in the lake! That is so unlike the Lake Superior I remember growing up in Duluth. Sure, we liked to spend a day on the sand beaches of Park Point or lounging on the rocky outcrops along the North Shore but swimming was usually not an option. On average, Lake Superior’s overall temperature is barely above freezing (39 °F), and back then it seemed you couldn’t even wade in ankle-deep without having your breath sucked out of your lungs and thinking your feet had fallen off. Standing knee-deep in the water for even a short time was unbearable and a true test of endurance. And for guys, going any further was just plain crazy, unless you wanted verifiable (and excruciating) proof of Costanza’sTheory of Shrinkage.
Those hell-bent among us would sometimes make a mad suicide dash across the burning sands and actually dive into the frigid waters only to set off the mammalian diving reflex and cause their vital organs to start to shut down. Their only hope was if the lifeguards were watching and were properly certified in CPR.
Temperature ranges on Superior have been recorded for more than three decades. In recent years, the normal average surface temperature for Lake Superior during the month of August has been only 55°, so this dramatic rise in the average is unusual. As expected, many people are quick to point a finger at global warming as the cause for the rise. That’s not a bad guess considering the National Oceanic and Atmospheric Administration (NOAA) just proclaimed the year 2010 as the hottest on record, globally.
But physicist Jay Austin at the University of Minnesota-Duluth’s Large Lake Observatory has been closely tracking the lake’s surface temperatures, and predicted the record high back in July. He says the warm water this summer is at least partially due to a recent El Niño event that had an unusual effect on the lake this past winter.
“2009 was a very strong El Niño year,” Austin said. “And that El Niño year led to a year at least on Superior where there was very little ice.”
That lack of ice led to a quicker and earlier warm up of Lake Superior’s surface waters. The other Great Lakes showed similar increases in their average warm temperatures as well. Although ice usually forms on the lake surface during the winter months, Lake Superior rarely freezes over completely. The last time was in 1979.
The following video illustrates the contrast between last winter and the one prior to that. Each day on their Coast Watch website, NOAA posts 3 or 4 photographs taken by a satellite in geosynchronous orbit above Lake Superior. Early in 2009 I began collecting the images regularly thinking they could come in handy for a future Buzz story such as this. From March 2009 to May 2010 I collected something like 1100 satellite photos. Edited together, they make for an interesting time-lapse video that illustrates the weather patterns over the big lake from one winter to the next. At the start of the video (March 2009) ice-cover is apparent over much of the lake and can be seen building then melting away as the spring thaw brings warmer temperatures. But later in the video, as summer passes into fall and fall into winter, no ice appears at all over the expanse of the lake’s surface. Other than that I don’t know how informative the time-lapse ended up being but it’s certainly interesting to watch, particularly the wind and cloud patterns seen flowing off the lake starting in late January 2010.
"This year is just tremendously anomalous," Austin said. "This year ranks up there with the warmest water we have ever seen, and the warming trend appears to be going on in all of the Great Lakes."
The big question is what effect these warmer temperatures have on the lake’s ecology? Austin admits it’s hard to say.
"Fish have a specific range of temperatures in which they like to spawn," he said. "It may be that for some fish this very warm year is going to be great for them, but for others, like trout which are a very cold-adapted fish, it's not going to be great."
One problem for the trout could be that scourge of the Great Lakes, the jawless sea lamprey. Lampreys are invasive parasites and attach themselves to lake trout and live off their blood. It’s unknown what changes, if any, the warmer waters will have on their life-cycle. They may lay eggs faster and in larger quantities, increasing their populations, and their impact on the trout species.
Lake Superior has probably passed through its peak time for temperature this summer so more than likely the 68.3°F record will stand for the rest of the year. If you want to keep track you can go to the Michigan Sea Grant website where you can follow all the Great Lakes’ daily surface temperatures. But who knows? This summer may not be the height of the 30-year warming trend. Let’s see what next year has in store.
Personally, I’m concerned these warm water temperatures will spoil us. Being able to endure extremely cold temperatures is a Minnesota tradition, and helps build character. It makes you tough and able to withstand all sorts of adversity as well as the harshest of elements. Which brings to mind the time when my wife (then girlfriend) and I were in Glacier National Park and decided to go for a swim in St. Mary’s Lake. There were only a few other people goofy enough to be swimming in the glacial lake at the same time. It didn’t surprise us to learn they were all from Minnesota.
We were so proud of ourselves.
Courtesy Nadir B
United Nation claims more than four million Pakistanis have been made homeless by nearly 3 weeks of flooding.
The number of Pakistani flood victims in need of urgent humanitarian relief has risen from six million to eight million, the U.N. said."
Outbreaks of cholera are common in large floods. Getting safe drinking water to many millions of people is urgent.
"We could have up to 140,000 cases of cholera," Sabatinelli (WHO) said. "We are preparing ourselves for that."
The after effects of this Pakistan flooding are worse than the 2004 Tsunami or the earthquakes in China and Haiti. Rebuilding roads, bridges, and buildings, and providing food, water and shelter to the many millions of flood victims is going to take billions of dollars.
Courtesy FundyAlong with wind and solar, harvesting power from tidal forces comes up a lot in discussions of alternative energy sources.
Was that a horrible sentence? I think it was. What I meant to say is this: we can generate electricity from tides, and lots of it. "Tidal power" is often brought up alongside solar power and wind power, but while I can easily picture windmills and solar panels, I'm not always sure what sort of device we'd use to harness the power in the tides.
This sort of device! For those of you too afraid to click on a strange link (who knows... I could be linking to an image like this!), the article depicts something that looks sort of like a thick, stubby windmill, with blades on its front and back. It's a tidal turbine, and at 74 feet tall and 130 tons it's the world's largest. It should be able to supply electricity to about 1,000 households. Pretty impressive.
Tidal turbines, apparently, are so productive because water is so much denser than water, and so it takes a lot more energy to move it. An ocean current moving at 5 knots (that's a little shy of 6 miles per hour, for the landlubbers) has more kinetic energy, for example, than wind moving at over 217 miles per hour.
At least according to that article, the United States and Great Britain each have enough tidal resources (areas where this kind of generator could be installed) to supply about 15% of their energy needs.
More info on the tidal turbine, which I am calling "the Kraken," because it's big, underwater, and will occupy your mind for only a very short time.
Courtesy Public domainA massive chunk of ice - 100 square miles of it – broke away from Greenland’s Petermann Glacier last week. The ice island is about 500 feet thick and contains enough fresh water to supply our entire nation’s tap water demands for 4 months and then some.
Just what the free-floating slab of ice will do next is anyone’s guess. Some scientist, such as Andreas Muenchow, a professor of ocean science and engineering at the University of Delaware are concerned it could get wedged in by actual islands dotting the Nares Strait between Greenland and Canada and jam up shipping lanes there.
"The newly born ice island may become land-fast, block the channel, or it may break into smaller pieces as it is propelled south by the prevailing ocean currents,” Muenchow said. “From there, it will likely follow along the coasts of Baffin Island and Labrador, to reach the Atlantic within the next two years."
A similar, huge slab of ice broke away from Greenland’s Ward Hunt Ice Shelf in 1962, and pieces of it became stuck in channel islands in the Nares Strait which is located about 600 miles south of the North Pole.
Muenchow has been keeping a watchful eye on the Petermann Glacier for the past several years and said he was expecting a calving to take place because the ice shelf had been growing. However, he wasn’t expecting one so large.
Although recent trends show a rise in global temperatures, Muenchow stops short of blaming the ice slab on climate change. "Nobody can claim this was caused by global warming. On the other hand nobody can claim that it wasn't," he said.
The Petermann Glacier is an ice shelf situated in northern Greenland covering an area of about 40 miles. The new ice island amounts to about twenty-five percent of the ice sheet. The following video from last summer shows why scientists were expecting last week’s event.
Courtesy Chris Fires and drought has destroyed so much of the wheat in Russia, that Prime Minister Vladimir Putin issued a ban on wheat exports for the rest of this year. Last year Russia exported more 17.5 million metric tons of wheat.
Pounding monsoon rains threaten to rot 17.8 million metric tons of wheat in India that are stored under tarps outdoors. Why they don't sell it at today's high prices or give it to the starving poor is supposedly explained in this quote:
Exporting the grain would be politically explosive because food inflation has been in the double digits for months. The government buying less wheat from farmers in a country where over half the population makes its living off the land is equally untenable. Selling more at subsidized prices to the poor is off the table because it would add to a swelling fiscal deficit. Associated Press
The United States is having a bumper yield this year and global wheat stockpiles are high. So why have Chicago wheat prices nearly doubled since June?
We fear that excessive speculation on wheat by bankers has led to the price soaring. Speculators have bought unusually high numbers of wheat contracts in recent weeks." ABC News