astronomy, weather

The Moon and Venus are getting closer (H. Michael Mogil, CCM, CBM, DMS)

If you happened to look to the west-southwest tonight just after sunset, and the clouds didn’t get in the way, you got to see the Moon catching up to Venus. Venus is the brightest planet in the sky right now and continues to impress in the evening sky.

The other night, a faint waxing crescent moon appeared on the western horizon just after the sun set. During the past two nights, as the sky darkened, the moon has become more easily visible in a position higher in the sky. Tonight, it lies just beneath Venus.

Mars, a very faint, reddish, planet by Venus’ standards, sits well above and slightly to the left of Venus.

All of these celestial bodies are annotated in Fig. 1 (image taken in Naples, FL).

Tomorrow evening, according to Earth & Sky, the Moon will sit above Venus, but below Mars.

Hope the clouds don’t ruin an impressive New Year’s sky show for my readers.

Enjoy!

© 2017 H. Michael Mogil

Originally posted 1/1/17

astronomy

THEWEATHERMOGIL:: Enroute to a solar minimum, Sun displays a large sunspot

Our Sun exhibits a periodic march from a minimum of sunspot activity to a maximum, and back again (Fig. 1). Right now we are deep in minimum territory. Still, solar activity can deviate from the larger scale cycling at any time.

Sunspot AR2529 has become quite a large sunspot (Fig. 2), doubling in size over the past weekend. The sunspot (the largest of 2016 to date) is now large enough to, figuratively, “swallow” the Earth.

NATL001-sunspot-cycles-1745-date  NATL002-sunspot-2529-160410

NASA’s Solar Dynamics Observatory (SDO) is keeping a close eye on this active sunspot region. Scientists at the SDO note that the magnetic fields near the sunspot’s core are crackling with minor C-class solar flares. While none of these flares is very strong, the ensemble of explosions is doing a good job heating the sun’s atmosphere above the sunspot. The towering “hot spot” is clearly shown in an extreme ultraviolet image taken by the SDO on Apr. 10, 2016 (Fig. 3).

NATL003-sunspot-2529-UV-image-160409

Despite its large size and state of unrest, Sunspot AR2529 has not yet launched a significant solar storm. It could still do, scientists note, should the sunspot continue to grow in size in the days ahead.

Here at the Global Weather and Climate Center, we’ll keep you posted on any changes to the sunspot and its potential impacts to Earth.

Sunspot Number computation information can be found here.

© 2016 H. Michael Mogil

Originally posted 4/11/16

astronomy, geography, geology, weather

THEWEATHERMOGIL:: When geology and meteorology meet

In the Earth-Space Science arena, we often discuss meteorology, hydrology, oceanography, astronomy and geology. In recent years, a curious blend of meteorology and astronomy, known as “Space Weather,” has emerged. The National Weather Service, now routinely issues “Space Weather” forecasts that address parameters such as the solar wind and the transport of electromagnetic surges toward Earth and our orbiting spacecraft. While not weather, as we know it Earth, its impacts are more weather-focused (electricity) than astronomy-based (planetary motions).

Another, not-so-unusual, relationship involves geology and meteorology. At the Earth-atmosphere interface, mountains and coastlines affect wind flow; mountains can lead to rain-shadow effects (wet on one side of the mountain and dry on the other); changes in elevation and/or the mountains themselves can lead to intense thunderstorm rainfall and flash flooding; and terrain, even without a mountain presence, can help to channel precipitation runoff into narrow canyons or waterways and lead to significant localized and/or deadly flash flooding.

Add volcanoes to the mix and now the geologic events themselves can cause meteorological impacts. The recent eruption of the Pavlof volcano in the Aleutian Island chain is a prime example (Fig. 1).

NATL001-USCG-Pavlof-ash-plume-tstorm-shape-160328-130pmAST?

First, any heating of the exterior or near exterior of a volcanic mountain (which in northern climes is often ice and/or snow covered), can lead to rapid snowmelt and cause avalanches, mudslides and/or flooding. It is easy to see the effect that melting has in this image of the Pavlof volcano (Fig. 2).

NATL002-USCG-Pavlof-ash-plume-flow-160328-319pmAST?

The main risk from volcanoes happens during and following an eruption. Based on the force of the ejected air and gas cloud, volcanic dust and particles can be lifted to altitudes high above the Earth’s surface. The Pavlof eruption of last weekend was relatively “tame,” sending ash only four to five miles aloft. The eruption of Mount Pinatubo (June 1991) sent ash so high that it reached well into the stratosphere, where ash was still detected years later.

The eruption process, once started, resembles the convective process of regular thunderstorm formation. In fact, volcanic clouds, as they grow from the eruption, often look like “dirty” thunderstorm clouds (towers, anvils, precipitation, virga and/or “fall” streaks, lightning and sometimes waterspouts). Fig. 1 and Fig. 3 typify what volcanic thunderstorms look like.

NATL003-USCG-Pavlof-ash-plume-160328-1117amAST?

In the short-term, volcanic ash and dust can lead to significant aviation impacts. In 1982, British Airlines Flight 9, flying at 37,000 feet, entered an ash cloud near Jakarta, Indonesia. The flight crew was not aware that such an ash cloud was in their flight path. As a result, the plane’s four engines “flamed out” and the plane started a growingly steep descent. The pilot was able to restart the engines, but not until the plane had descended to 12,000 feet. Following another “flame out” of one engine, the pilot was able to safely land the plane. A review following the incident demonstrated that the ash cloud was associated with an eruption from Mount Galunggung, some 110 miles southeast of Jakarta.

A similar experience occurred in late 1989 following an eruption of Mount Redoubt, AK. Here, a KLM flight, carrying 231 passengers to Anchorage, suffered a drop of several thousand feet following a “flame out” of its engines.

Since the ash cloud plume from the recently-erupted Pavlof volcano extended several hundred miles into Alaska (Fig. 4), flight operations at Alaska Airlines were put on hold (41 cancellations) on Monday. With the volcano eruption lessening, and the threat level lowered accordingly, flight operations at Alaska Airlines are expected to resume yesterday.

NATL004-GOES-Pavlof-ash-plume-160328-1900Z

As noted by Alaska Airlines spokeswoman Bobbie Egan, and most likely echoed by every airline executive worldwide, “We just simply will not fly when ash is present.”

Now, the United States Geologic Survey (USGS) routinely monitors volcanoes for all types of hazards and issues advisories or alerts for a wide range of target audiences. The USGS and other agencies use a sophisticated array of sensors to track earth movements, changes in lava distribution and aircraft to monitor actual or imminent eruptions. In the U.S., NOAA routinely provides satellite support, helping to track any ash clouds and monitor their density. Worldwide, a total of 9 Volcano Ash Advisory Centers (VAACs) provide such support for international aviation. The bottom line is that flight cancellations rather than emergency landings or actions are now the rule.

Although the Pavlof volcano has calmed down a bit and alert levels have been lowered, Pavlof and several other volcanoes worldwide remain on active USGS monitoring lists.

© 2016 H. Michael Mogil

Originally posted 3/30/16; updated 3/31/16

astronomy, weather

Wet v. dry and more

Astronomical spring starts today, Fri., Mar. 20 at 6:45 p.m. E.D.T. Although the weather has recently turned or remained spring-like (or warmer) in some places, winter is not yet out of the picture.

First, it is important to recognize that for yet another winter season, California and other parts of the southwest U.S. failed to receive much needed rainfall…To read the entire feature, click here.

Originally published 3/20/15

"Life", astronomy, biology, education, geology, hydrology, learning, nature, oceanography, photography

Bing’s homepage images return excitement to learning

There’s probably not a better way to get a brain engaged first thing in the morning than to use the Bing home page. Each day, Bing (a Microsoft-based search engine) features an incredible homepage image involving something from nature and the Earth, the human sphere, architecture, and other categories. Images range from…To read the entire feature, click here.

Originally published 3/12/15

astronomy, climate, climate change, general, learning, mathematics, movie reviews, tutoring, weather

Hello world!

Welcome to my WordPress Article Catalog. Here you will find hundreds of postings about weather, math, learning, tutoring and more.  If it’s on my mind, then it may soon be coming to an online article near you.

Feel free to comment on any of my articles.

Feel even freer to pose questions or suggest topics for future articles.

Thanks for reading and I hope you enjoy.

H. Michael Mogil, CCM, CBM, tutor, life-long learner, more…