The Hole at the South Pole

The Ozone Hole

Earth's ozone hole, from data provided by NASA's Goddard Space Flight center and the Ozone Hole Watch. The blue area is the 'ozone hole', where the density of the ozone layer is at its thinnest this time of year.

One of the best things that NASA does (along with other space agencies) is give us a look at our own planet — as a planet.  That is, the scientists who study our world do so in the same way they would study any other planet. They chart changes on the surface, map atmospheric activity, and chart all those changes over time.  For the past decades, scientists have charted something called the ozone hole, which forms over the south pole of our planet each year.  This image shows what the ozone looks like as of September 13, 2010, courtesy of the OzoneWatch website.

Satellite instruments monitor the ozone layer, and scientists use the data to create the images that indicate the amount of ozone in the upper atmosphere. The blue and purple colors are where there is the least ozone, and the greens, yellows, and reds are where there is more ozone.  The depth and size of this Antarctic ozone hole are affected by the temperature of the stratosphere (the upper part of Earth’s atmosphere) and the amount of sunlight that bathes the south polar region.

So, why is ozone such an important thing to monitor? This is a useful gas for the protection of life on this planet.  In the upper atmosphere, ozone acts to absorb ultraviolet-B emissions.  Such emissions, which come primarily from the Sun, can harm living systems. It’s safe to say that, without the ozone layer in our upper atmosphere, life on Earth would be severely harmed.  In fact, without the ozone layer, it’s possible that life wouldn’t have formed on this planet.  So, losing a chunk of our ozone layer each year is a big deal.  Scientists want  understand why this happens.

Now the good news is that the ozone layer is not thinning anymore — after more than half a century of actively thinning.  This is due to a ban on harmful chemicals that have damaged the ozone  layer.

We know that ozone is destroyed by chlorine- and bromine-containing chemical compounds.  We know that some aircraft emissions hurt the ozone layer.  We know a lot of different reasons why our ozone layer is under attack, not just from the Sun, but from below by the sentient life forms that inhabit the planet.

Sure, there are naturally occurring attacks on the ozone, but the largest attack comes from human activity. We use huge amounts of chemical compounds in industrial and home-based products. You may have heard of what’s referred to as chlorofluorocarbons. They escape to the atmosphere from refrigeration and propellants.  They persist for years in the lower part of the atmosphere, and eventually some migrate to the upper atmosphere. It’s a long-term process because the destruction of ozone doesn’t happen the minute CFCs get into the atmosphere.  But, it does eventually happen. So, even though we HAVE reduced our use of these compounds — the damage from the reservoir of ozone-destroying atoms and molecules has continued.  The damage that now shows up in the ozone hole probably comes from materials released well into the last century. With luck, and the continued ban on these chemicals, the ozone should get back to its 1980 levels by mid-21st century.

I know that there are still people who deny such problems existed — generally they are people who don’t want to believe that humans can have a deleterious effect on our planet’s ecosystems. The problems won’t go away because some people bury their heads in the sand. Oh, sure, their faces won’t get sunburned by the UV-B, but their hineys will.

So, what’s the effect of the loss ozone? Ask the people who live under that hole and who are at higher risk for cancer and other conditions that are caused or exacerbated by exposure to ultraviolet-B.  I was in South America a few years ago, at the very tip of the continent. The people who live there know first-hand what it’s like to live under a thinning ozone layer.  Sunblock is a constant friend.  Children are warned NOT to go out with out adequate clothing and sunblock.  If you want to know what life would be like on this planet with a thinner (or nearly nonexistent) ozone layer, talk to the children of Patagonia.

And, thanks to NASA and other agencies who continually monitor our planet from space (another fine example of how space exploration benefits us here at home), we might be able to learn enough to avoid dissipating our ozone layer more than it already is.

Observe the Moon

You Can’t Miss It!

The Moon, as seen from the International Space Station. Courtesy NASA.

Do you like to look at the Moon?  It’s a great object to study — whether with the naked eye or binoculars, or with a telescope (if you have one).  On September 18 (this Saturday), all the Moon gazers around the world will join together to celebrate the first of what they hope will be many “International Observe the Moon Nights“.

The Moon is so close, yet so far away from us.  It takes about  1.3 seconds to send a light beam between Earth and the Moon. If you wanted to travel there, it would take more than a day (and more likely a couple of days at the least). And, once you got there, you’d have to live in a space suit, bring along your own food and water, and — if you wanted to build a home there — you’d have to live underground for your own safety.  The lunar surface is covered with craters and coated with dust. It’s not very hospitable at all — but, humans have wanted to travel there. And, in the 1960s and 1970s, humans DID go to the Moon.  We aren’t back there yet, but hopefully someday we will be.  It’s a worthy goal for any traveler. For now, though, we can observe it easily from our backyards.  Hence, the celebration of International Observe the Moon Night.

The best part about the celebration is that you don’t have to be an experienced skygazer.  It’s for anybody — from the general public to amateur astronomers to professionals — to gaze at the Moon.  Check out the festivities at the link above — where you’ll find a history of the event and some forms to fill out if you participate.  I can’t think of a better way to spend a September evening! Can you?

That Which is Done Beneath the Naked Stars

Is Never Forgotten

The view west of Boulder Colorado at night, looking north, with a backdrop of flames from the Four Mile Fire. Image courtesy of MyTownColorado.com and William Maher III. Click to enlarge.

I think this picture speaks for itself, but in case you haven’t been following the news in Colorado, we are witnessing a wildfire that has (as of this writing) destroyed at least 93 buildings (homes and other structures), spread across more than 7,000 acres, and caused the evacuation of thousands of people.  It began on September 6 around 10:30 a.m. and spread quickly. Many of us who are outside the danger zone but close enough to see have been taking photographs of the fire. I live about 9 miles south of the fire and we’ve watching the huge clouds of smoke during the day and the glowing sheets of flame at night (when visible).  This is one of the most spectacular, clearly showing the naked stars over the fire scene.  It was taken by William Maher III, probably on September 6, 2010.  You can see more images at MyTown Colorado.

I’ve posted some of my own pictures taken on the first day of the fire here (FB mirror here).