Category: Environment & Weather

A Postcard to the Pacific Northwest: Prepare

The average time between magnitude 8 and larger Cascadia earthquakes is about 240 years … . The last megaquake, estimated as a magnitude 9, occurred in 1700 — that’s 311 years ago. In geologic terms, Cascadia is “9 months pregnant” and overdue.

Earthquake expert Yumei Wang quoted at Dot Earth, The New York Times.

The Cascadia Subduction Zone is off the northern California, Oregon, Washington and British Columbia coasts. One of the reasons we know of the great quake in 1700 is because they recorded the tsunami from it in the very parts of Japan hardest hit Friday.

There are a lot of variables, but a magnitude 9 earthquake is roughly half again as powerful as Friday’s 8.9.

Why Are Birds Falling From the Sky?

But the in-air bird deaths aren’t due to some apocalyptic plague or insidious experiment—they happen all the time, scientists say. The recent buzz, it seems, was mainly hatched by media hype.

At any given time there are “at least ten billion birds in North America … and there could be as much as 20 billion—and almost half die each year due to natural causes,” said ornithologist Greg Butcher, director of bird conservation for the National Audubon Society in Washington, D.C.

National Geographic Daily News

The first solar eclipse of 2011

Yesterday a partial solar eclipse took place, observable through most of Europe and northwestern Asia. Over parts of Europe, as much as two-thirds of the sun slipped from view behind the moon. The region that saw the greatest eclipse was in northern Sweden. This was the first of four partial solar eclipses which will occur in 2011, the others taking place on June 1st, July 1st and November 25th. Collected here are photographs of yesterday’s celestial event and observers here on Earth as they tried to catch a glimpse. (24 photos total)

The Big Picture – Boston.com

Watch out for the Super Harvest Moon

For the first time in almost 20 years, northern autumn is beginning on the night of a full Moon. The coincidence sets the stage for a “Super Harvest Moon” and a must-see sky show to mark the change of seasons.

The action begins at sunset on Sept 22nd, the last day of northern summer. As the sun sinks in the west, bringing the season to a close, the full Harvest Moon will rise in the east, heralding the start of fall. The two sources of light will mix together to create a kind of 360-degree, summer-autumn twilight glow that is only seen on rare occasions.

Keep an eye on the Moon as it creeps above the eastern skyline. The golden orb may appear strangely inflated. This is the Moon illusion at work. For reasons not fully understood by astronomers or psychologists, a low-hanging Moon appears much wider than it really is. A Harvest Moon inflated by the moon illusion is simply gorgeous.
The view improves as the night wears on.

Northern summer changes to fall on Sept. 22nd at 11:09 pm EDT. At that precise moment, called the autumnal equinox, the Harvest Moon can be found soaring high overhead with the planet Jupiter right beside it. The two brightest objects in the night sky will be in spectacular conjunction to mark the change in seasons.

NASA Science

Right now the sky here in sunny New Mexico is overcast. May we all be blessed with clear skies this evening.

Close Encounter

Been outside at midnight lately? There’s something you really need to see. Jupiter is approaching Earth for the closest encounter between the two planets in more than a decade–and it is dazzling.

The night of closest approach is Sept. 20-21st. This is also called “the night of opposition” because Jupiter will be opposite the sun, rising at sunset and soaring overhead at midnight. Among all denizens of the midnight sky, only the Moon itself will be brighter.

NASA Science

It’s the closest we’ll be to Jupiter (or Jupiter to us if you prefer) until 2022. Don’t miss it — and take the kids. Kids remember things like this. You don’t have to wait until midnight. Look east after sunset; higher in the sky as the night progresses.

Thanks to Ah, Wilderness! for the link and the reminder.

UPDATE: Jupiter is really quite brilliant, even with moonlight filling the sky.

Smallest Full Moon of 2010

Tonight’s full moon (it actually became full at 11:05 AM MDT) will be the smallest looking of the year. That’s because tonight it will be at apogee, the most distant point in its monthly elliptical orbit around Earth.

There’s about a 12% variation in how large the moon appears when it is full at perigee (closest) and when it is full at apogee (farthest) like tonight. Tonight’s full moon is much dimmer too.

The moon was about 31,000 miles closer to us during 2010’s brightest full moon. That was January 29th.

Hot, you call this hot, well back in the old days . . .

On this day in 1936, the Dust Bowl heat wave was so intense that Kansas and Nebraska experienced their all-time hottest temperatures, unbroken to this day. In Alton, Kansas, the temperature was 121 degrees, and in Minden, Nebraska, it was 118.

During the summer of 1936, a total of 15 states recorded all-time hottest temperatures that still have not been broken. And not all of the states were in the Dust Bowl region. Earlier in the month, Runyon, New Jersey, was 110, Moorhead, Minnesota, hit 114, and Martinsburg, West Virginia, 112. By early August, Ozark, Arkansas, and Seymour, Texas, had hit 120 degrees.

The term “Dust Bowl” had first been used on April 15, 1935, the day after “Black Sunday,” when dust storms were so bad on the Great Plains that the sky was totally black during the day and there were winds up to 60 miles per hour.

The Writer’s Almanac with Garrison Keillor

Here’s a list of the 50 state records. I count 13 all-time highs from 1936.

Linkage

Joe Posnanski on What 600 Homers Means. A lot less than it used to, he concludes.

And The Big Picture shows some recent work of Mother Nature.

In the past several months, powerful storms have wreaked havoc in many places, torrential rains in central Europe and parts of China, tornadoes in Australia, Montana and the American Midwest, and strong thunderstorms across the northeast. Now, as Tropical Storm Bonnie makes landfall in Florida and heads into the Gulf of Mexico, oil cleanup is being suspended, and the final “kill” operation is delayed for at least one more week. These storms have been destructive and deadly, but beautiful and awe-inspiring at the same time. Collected here are a handful of photographs of stormy skies, lightning strikes and storm damage from the past several months. (37 photos total)

Oil in the Gulf, two months later

62 days have passed since the initial explosion of BP’s Deepwater Horizon drilling rig in the Gulf of Mexico, and the crude oil and natural gas continue to gush from the seafloor. Re-revised estimates now place the flow rate at up to 60,000 barrels a day – a figure just shy of a worst-case estimate of 100,000 barrels a day made by BP in an internal document recently released by a congressional panel. Louisiana’s state treasurer has estimated environmental and economic damages from the Gulf of Mexico oil spill could range from $40 billion to $100 billion. Collected here are recent photographs from the Gulf of Mexico, and of those affected by the continued flow of oil and gas into the ocean. (37 photos total)

The Big Picture – Boston.com

Solstice II

In the northern hemisphere, summer began at 5:28 AM MDT (11:28 UTC).

It’s the longest day of the year for locations north of the equator. The further north, the more daylight. That means 14 hours and 31 minutes of daylight in Albuquerque, 14 hours and 59 minutes in Denver, Colorado, 15 hours and 44 minutes in Billings, Montana, and 21 hours 50 minutes in Fairbanks, Alaska.

[Sunrise today in Fairbanks was at 2:57 AM. Sunset tonight will be at 12:47 AM Tuesday. Of course, with twilight, it is light all night.]

What this means astronomically speaking is that at 06:46 Universal Time today (June 21) the northern hemisphere of the earth was tilted 23.4° toward the sun; the southern hemisphere was tilted 23.4° away.

This is best explained with an orange and a flashlight.

Sunrise Solstice at Stonehenge (2008). Click for larger version and to learn more.

Solstice

A good summary about the solstice from National Geographic begins with this:

The summer solstice is a result of the Earth’s north-south axis being tilted 23.5 degrees relative to the sun. The tilt causes different amounts of sunlight to reach different regions of the planet.

Today the North Pole is tipped closer to the sun than on any other day of 2010. The opposite holds true for the Southern Hemisphere, for which today is the winter solstice, the shortest day of the year.