[Intro] You remember the difference between weather and climate, right? If not, this month is a good time to learn the difference. If you live anywhere in North America, you’re probably coming out of one of the earliest and longest cold snaps you can remember. Records were broken or tied all over the Midwest, Northeast, and South as a wall of arctic air brought a week and a half of subfreezing temperatures. But that and whatever else is going on outside your window right now is weather, the short-term conditions of the atmosphere wherever you are. By contrast, patterns of weather across bigger areas and over years and decades and centuries is climate. And for sure, it can be hard to square the weather your neighborhood is experiencing with the larger trends of climate, because, for example, even though it may not feel like it right now, 2014 is shaping up to be the warmest year on record.
The Earth, the entire Earth, just had its warmest October ever, according to new data from NASA and the Japanese Meteorological Agency. The months of April, May, June, August, and September were also the warmest on record, going back to the 1800s. And this includes the oceans, which have been causing a lot of confusion when it comes to global warming. Despite rising greenhouse gas levels, the ocean’s surface temperature has remained relatively steady since the year 2000. This phenomenon has come to be known kind of unfortunately as the global warming hiatus, and it marked a slowdown in the rise of overall global temperature as well. The hiatus wasn’t predicted by climate models in the 1990s, which, of course, led some people to say that all of climate change prediction must be faulty. But global warming never actually paused during this so-called hiatus.
Instead, it turns out that the heat was absorbed deep within the ocean. Most scientists think this happened because of something called the Interdecadal Pacific Oscillation, or IPO. This is a natural fluctuation in atmospheric pressure over the Pacific ocean, and it has two modes, high and low, switching between the two every ten to thirty years. When the IPO is low, trade winds accelerate along the equator and cause heat from the surface to sink deeper into ocean waters, while bringing colder water to the surface. When the IPO is high, these winds weaken, and all that heat rises back to the surface. Since 1999, the IPO has been in low mode, making the oceans unusually cool, at least at the surface. Now there are signs that the IPO has finally switched into high gear. According to new data from the International Pacific Research Center in Hawaii, the North Pacific began to warm in January, and then throughout the spring, all the heat trapped in the deep ocean rose to the surface and began expanding.
By summer, the mean surface temperature of the world’s oceans was the highest it’s ever been since recording began in the mid-1800s. And that heat continued to rise into the atmosphere, which might explain why we just saw the warmest October on record. So yes, the warmest October ever, followed by one of the coldest Novembers, is weird. But so is saying that global warming was on “hiatus” when really it wasn’t. Now, we humans are really good at taking inspiration from nature when we want to invent something cool; it’s called bionics. When we wanted to fly, we studied birds. When we wanted to swim faster, we studied frogs. Now, we’re taking a page from geckos. The U.S. Department of Defense, along with Draper Laboratory, revealed this week a pair of hand-held climbing paddles they’ve invented that are inspired by geckos’ feet. It’s said to be the first bionic technology that allows people to climb walls of glass. Geckos are some of the best climbers in the world. They can run up windows and hang from ceilings.
Their toes are adhesive, but not like tape, which is pressure-sensitive. Geckos can actually turn off the stickiness of their toes. Each toe is covered with millions of tiny hair-like strands, called setae. Each strand, in turn, branches off into hundreds of individual bristles, called spatulae, kind of like your paintbrush. These spatulae are so small that they can fit inside of the contours of what looks like a smooth surface, like glass. They can also form weak electrostatic bonds with the molecules in the glass. This attraction is called the Van Der Waals force, and billions of these attractions at the molecular level can get a gecko to stick to just about anything, until it breaks the bond by lifting its foot. To scale up the Van Der Waals force for human use, defense scientists build hand-sized paddles covered in billions of nano fibers called micro-wedges.
These wedges were made of a silicon-based polymer, which, like a gecko’s spatulae, can bond through Van Der Waals forces when pressed on a smooth surface. Using just these paddles, a 90-kilogram man was able to climb almost 8 meters up a glass surface. The defense department says these paddles can be used in places like war zones, when soldiers need to climb a building without ropes or ladders, but I always end up thinking of other applications for this type of technology, most of which involve fighting crime in skintight suits. Though somehow, “The Amazing Gecko-Man” doesn’t have the same ring to it. Thanks for joining me on this week’s Scishow News. If you want to help us share science with the world, you can become a supporting subscriber at Subbable.com/SciShow. There, you can get SciShow swag, like a key-chain, laptop decal, or t-shirt, but no amazing gecko-man suits.
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