Tonight on NOVA: "Japan's Killer Quake"

Tonight on NOVA, an in-depth scientific examination of Japan's recent earthquake, the subsequent tsunami, and the continuing nuclear incident. Entitled (perhaps indelicately) Japan's Killer Quake, the program shows plenty of footage that was new to me -- including a particularly surreal clip apparently shot on a mobile phone, showing a crack in the concrete opening and closing, over and over. It's like a movie special effect -- except it's real, and thus really horrifying. The program airs tonight (Wednesday, March 30, 9pm Eastern/8pm Central) on PBS stations across the US. Check your local listings, as NOVA has moved to Wednesday nights.

I've watched the episode twice, but I'm still not sure what to say about it. I'm still in shock, weeks after the earthquake. The scale of the tragedy is so unimaginable that seeing it on film doesn't make it any easier to accept -- though having scientists explain it certainly helps to understand what happened. Throughout the program, I had a feeling that, although scientists were explaining the disaster, and reporters on the ground were showing its effects, I simply could not emotionally process what I was seeing. Near the end of the program, as the nuclear crisis was discussed, things seemed even worse.

Finally, the program forces us to examine the threat of future earthquakes -- apparently there is danger of a similar earthquake much closer to Tokyo, which would be far more deadly. For my part, I live in the Pacific Northwest of the US, where a massive earthquake has long been predicted, based on historical evidence of previous "mega-quakes" along the volatile Cascadia fault. My house is nearly a hundred years old, and is not built to survive a serious earthquake, and certainly not the magnitude 8 or 9 quake we can expect...eventually. "[Japan's earthquake] is really a template for what might occur on the northern coast of Oregon and Washington. We know we are expecting an almost identical-sized earthquake [along the Cascadia fault]," says a scientist in the NOVA episode. Another scientist points out that the US is, at best, decades away from the Japanese in earthquake preparedness -- and we can't predict when a magnitude 9.0 earthquake will occur in my neighborhood. We just know that it will.

Here's a preview of tonight's NOVA episode:

I do recommend this program, particularly if you haven't kept up with the earthquake news. It does not show gory stuff -- this is a program about science, not shock value -- but it does show plenty of tsunami footage, as well as cleanup crews who are searching for bodies. (The bodies aren't visible; they're buried under mud. It's truly horrible.) I would suggest keeping young kids away from this one until you've had a chance to preview it -- unless you're ready to have a sober discussion about disaster preparedness.

After the jump, another clip from tonight's NOVA.

Original image
Growing Up With Headphones May Not Damage Kids’ Hearing
Original image

A study published in the American Medical Association's JAMA Otolaryngology-Head & Neck Surgery finds no increase in child and adolescent hearing loss despite a rise in headphone and earbud use.

"Hearing impairment in children is a major public health burden given its impact on early speech and language development, and subsequently on academic and workforce performance later in life," the authors write. "Even mild levels of hearing loss have been found to negatively affect educational outcomes and social functioning."

As portable music players continue to grow in popularity, parents, doctors, and researchers have begun to worry that all the music pouring directly into kids' ears could be damaging their health. It seems a reasonable enough concern, and some studies on American kids' hearing have identified more hearing loss.

To take a closer look, researchers at the University of California-San Francisco analyzed data from the National Health and Nutrition Examination Survey (NHANES), collected from 1988 to 2010. They reviewed records from 7036 kids and teens between the ages of 12 and 19, checking each participant's hearing tests against their exposure to noise.

As expected, the authors write, they did find a gradual increase in headphone use and other "recreational noise exposure." And they did see an uptick in hearing loss from 1988 to 2008 from 17 percent to 22.5 percent. But after that, the trend seemed to reverse, sinking all the way down to 15.2 percent—lower than 1988 levels. They also found no significant relationship between noise exposure and hearing loss.

The results were not uniform; some groups of kids were worse off than others. Participants who identified as nonwhite, and those of lower socioeconomic status, were more likely to have hearing problems, but the researchers can't say for sure why that is. "Ongoing monitoring of hearing loss in this population is necessary," they write, "to elucidate long-term trends and identify targets for intervention."

Before you go wild blasting music, we should mention that this study has some major limitations. Hearing loss and other data points were not measured the same way through the entire data collection period. Participants had to self-report things like hearing loss and health care use—elements that are routinely under-reported in surveys. As with just about any health research, more studies are still needed to confirm these findings.

Original image
Weather Watch
NASA Figures Out Why When It Rains, It (Sometimes) Drizzles
Original image

What’s the difference between drizzle and rain? It has to do with updrafts, according to new research by NASA scientists into the previously unexplained phenomenon of why drizzle occurs where it does.

The answer, published in the Quarterly Journal of the Royal Meteorological Society, could help improve how weather and climate models treat rainfall, making predictions more accurate.

Previously, climate researchers thought that drizzle could be explained by the presence of aerosols in the atmosphere. The microscopic particles are present in greater quantities over land than over the ocean, and by that logic, there should be more drizzle over land than over the ocean. But that's not the case, as Hanii Takahashi and her colleagues at the Jet Propulsion Laboratory found. Instead, whether or not rain becomes full droplets or stays as a fine drizzle depends on updrafts—a warm current of air that rises from the ground.

Stronger updrafts keep drizzle droplets (which are four times smaller than a raindrop) floating inside a cloud longer, allowing them to grow into full-sized rain drops that fall to the ground in the splatters we all know and love. In weaker updrafts, though, the precipitation falls before the drops form, as that light drizzle. That explains why it drizzles more over the ocean than over land—because updrafts are weaker over the ocean. A low-lying cloud over the ocean is more likely to produce drizzle than a low-lying cloud over land, which will probably produce rain.

This could have an impact on climate modeling as well as short-term weather forecasts. Current models make it difficult to model future surface temperatures of the Earth while still maintaining accurate projections about the amount of precipitation. Right now, most models that project realistic surface temperatures predict an unrealistic amount of drizzle in the future, according to a NASA statement. This finding could bring those predictions back down to a more realistic level.


More from mental floss studios