Solar activity only a minor factor in global warming
By Summit Voice
FRISCO — The sun’s activity is only a minor factor in 20th century global warming, a new study once again confirms, shooting down one of the red-herring arguments put forth by climate science deniers.
At most, solar cycles have contributed no more than 10 per cent to global warming in the last century. The findings, made by Professor Terry Sloan at the University of Lancaster and Professor Sir Arnold Wolfendale at the University of Durham, find that neither changes in the activity of the Sun, nor its impact in blocking cosmic rays, can be a significant contributor to global warming.
“Our paper reviews our work to try and find a connection between cosmic rays and cloud formation with changes in global temperature,” Sloan said. “We conclude that the level of contribution of changing solar activity is less than 10 per cent of the measured global warming observed in the twentieth century. As a result of this and other work, the IPCC state that no robust association between changes in cosmic rays and cloudiness has been identified.” Continue reading “Climate: So much for the cosmic ray theory”→
Tuesday’s sunset the earliest of the year; afternoons will start getting longer on Dec. 12
By Bob Berwyn
SUMMIT COUNTY — If you’re tired of the sun setting behind the western mountains in the middle of the afternoon, fear not, there’s some relief in sight. As of today (Dec. 4) the sun has completed its southward peregrination along the western horizon, which means the afternoons won’t get any shorter.
FRISCO — After a few late-summer snowfalls, there’s little doubt that change is in the air, and nothing marks that more than Saturday’s autumnal equinox, when summer turns to fall, and the nights start growing longer than the days. Technically, the equinox isn’t a day, but a single moment in time (:49 a.m.) when the sun crosses the equator, so to say, from north to south, when the Earth’s axis is tilted neither away from, nor toward the Sun. Day and night are about equal lengths in both the northern and southern hemisphere, and the sun passes directly overhead at the equator.
As Wikipedia puts it, “The equinox … is a precise moment in time which is common to all observers on Earth.”
Trace the path of the sun across the sky the next few weeks. You’ll notice that, by the middle of October, it will much farther south than it is right now, and, of course, lower in the sky. In observance of the day, the Slooh space camera will stream a free webcast of live shots of the sun from telescopes around the world.
SUMMIT COUNTY — It may not be quite as sexy as the recent lunar eclipse, or as spectacular as the this morning’s meteor shower, but Earth nonetheless experiences another celestial milestone today when it reaches it’s closest point to the sun during its 365-day orbit.
To be precise, at perihelion, our planet will close in to within about 91 million miles of the sun, more than 3 million miles closer than at the early July aphelion, when the the Earth and sun are more than 94 million miles apart. All this because, of course, the Earth’s orbit is elliptical and not circular. Continue reading “Sky Watching: Happy Perihelion!”→
SUMMIT COUNTY — I’ve always thought that sunset is a great time to drop what you’re doing and reflect for a few minutes. Watching the sun slip below the horizon really gives me a sense of the inexorable spinning of our globe, and with that, the full reality that time never stops. Each day is a gift, and sunset is the perfect moment to consciously appreciate it. Next time you notice those dusk colors getting deeper in the sky, think about shutting down your computer, turning the TV off and spending a few moments outside, reflecting on the grace we’ve been given.
All the shots were taken on Manasota Key, in Englewood Florida.
SUMMIT COUNTY — It wasn’t quite as sexy as the lunar eclipse, or as spectacular as the recent meteor shower, but Earth nonetheless experienced a milestone of sorts with the Jan. 3 perihelion.
To be precise, our planet closed in to within 91.4 million miles of the sun at 11 a.m. Mountain Time, more than 3 million miles closer than at the early July aphelion, when the the Earth and sun are more than 94 million miles distant.
This year, aphelion will coincide with our Independence Day celebrations on July 4, when the Earth will be 94.5 million miles away from the sun. All this because the Earth’s orbit is not circular — it’s elliptical.
It may seem counter-intuitive that the Earth is closer to the sun during the coldest time of the year, but the temperatures at the surface of the planet are influenced by the 23.5 degree tilt of the Earth’s axis and the angle of the sun’s rays. Because of that tilt, the northern hemisphere days are much shorter in our winter, leading to the colder temperatures. Continue reading “Happy (belated) perihelion!”→