Tag Archives: climate change

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We aren’t the dinosaurs: we’re the asteroid

[ This blog is dedicated to tracking my most recent publications. Subscribe to the feed to keep up with all the science stories I write! ]

The Sixth Extinction: We’re Not The Dinosaurs, We’re The Asteroid

Yes, humans are probably to blame for the Earth’s sixth mass extinction event, which is wiping out species at a rate 53 times greater than normal.

For The Daily Beast:

Extinction is an inevitable consequence of evolution. Environments change, new species arrive and crowd out the old, any number of factors make a formerly successful species unsuccessful. No less an authority than Charles Darwin wrote in The Origin of Species, “Natural Selection almost inevitably causes much Extinction of the less improved forms of life and induces what I have called Divergence of Character.”

Even without the 19th-century capitalization for emphasis, extinction is a big deal. Earth has experienced at least five major mass extinction events, of which the end of the dinosaurs wasn’t even the largest. (The end of the dinos that hadn’t evolved into birds, of course.) Now the planet is experiencing the sixth mass extinction, and growing evidence points to the culprit. It’s not asteroids or volcanoes or methane this time.

It’s us. [Read the rest at The Daily Beast….]

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Blogging about science for Forbes Magazine

[ This blog is dedicated to tracking my most recent publications. Subscribe to the feed to keep up with all the science stories I write! ]

As of this week, I will be blogging regularly for Forbes on planetary science, climate change, physics, and math. My first two posts are up; go check them out and please follow my blog!

Why are Pluto’s moons so weird?

Pluto is a strange little world, but its moons are even weirder.

Whether or not you want to call it a “planet”, it’s a body strongly influenced by two other worlds: the giant planet Neptune and its moon Charon. Pluto crosses Neptune’s orbit twice during its long sojourn around the Sun. But Charon (which I pronounce KAR-on, but you’ll also hear SHAR-on and other variations) is the big deal: the moon is more than 10 percent of the mass of Pluto. It exerts such a strong gravitational pull that both objects orbit a spot in empty space between them, and forces Pluto to present one face to Charon, just like Earth forces the Moon to keep the same side faces us. If you lived on the “far side” of Pluto, you’d never see Charon in the sky.

Pluto and Charon together have four much smaller moons: Styx, Nix, Kerberos, and Hydra. We don’t know much about those moons yet: Nix and Hydra were only discovered in 2005, Kerberos was found in 2011, and Styx in 2012. Even in our most powerful telescopes, they appear as dots. (Pluto and Charon aren’t much better off — they look like blurry disks even to the Hubble Space Telescope.) But looking at their orbits around Pluto and Charon, astronomers found something weird.

Those tiny moons dance in tandem. [Read the rest at Forbes…]

New analysis shows Earth is warming faster than we thought

Politicians may dither and talking heads bloviate, but the scientific consensus is clear: climate change is real, humans are responsible, and its effects are already being felt around the world. At the same time, some details are in question, including how fast climate change is increasing and which specific effects we see are due to it as opposed to other sources.

That’s the context for a new paper in Science today from researchers at the National Oceanographic and Atmospheric Administration (NOAA, which is somewhat ironically pronounced “Noah”). Thomas Karl and colleagues took a second look at global surface temperatures — the ordinary temperatures we’re used to seeing on weather news or in our phone apps — and found the official numbers on rising temperatures are too low. To put it another way: the consensus opinion is that we are currently in a global warming “hiatus”, but Karl and coauthors report instead that temperatures are climbing as fast as ever.

As if we didn’t have enough to worry about. [Read the rest at Forbes…]

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Slowing light to measure the creep of glaciers

[ This blog is dedicated to tracking my most recent publications. Subscribe to the feed to keep up with all the science stories I write! ]

My most recent article is an interesting combination of fundamental quantum physics research — the slowing of light inside specially-designed materials — with the study of the impacts of climate change on Greenland glaciers.

How to clock a glacier

From Nautilus:

low-flying airplane buzzes along the coast of Greenland, hovering over a glacier. The belly of the plane holds a laser that bounces light off the glacier’s face. As the light beam returns to the plane, it enters a black box that slows it to a crawl, turning it into a moment-by-moment report on the glacier’s speed. Each flight, each glacier measured, allows researchers to map the diminishment of the Greenland ice cap. Similar planes skirt Antarctica and the coast of Alaska, charting the damage to the ice cover.

These airplanes and their experimental equipment don’t exist yet. But the need to measure glacier flow in real time does exist. The latest report by Intergovernmental Panel on Climate Change (IPCC) projected that melting ice may result in as much as one meter of sea-level rise by the year 2100, threatening millions of people in low-lying nations and coastal cities. Knowing how glaciers melt can help researchers predict the future. But glaciers are, well, glacial. Most of them creep roughly two to three kilometers each year, covering less distance than most of us can walk in an hour. The fastest ice flow in Greenland is the glacier Jakobshavn, which moves at the blazingly slow speed of about 16 kilometers in a year—about 180 centimeters per hour. [Read the rest at Nautilus]

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Two weeks in review (October 27-November 9)

The Universal Marathon: 13.8 billion years! You run this race whether you like it or not, so might as well enjoy it.

Evidently I forgot to post one of these roundups last week, so here’s two weeks’ worth of writing all at once! Also, I have a new sticker design you can order, for those of you (like me) who don’t willingly run for exercise, but want to feel you’ve accomplished something anyway. At least in a cosmological sense, we all run this marathon we call existence.

  1. Drown your town, drown the world (Galileo’s Pendulum): My colleague Andrew David Thaler asked how much water would be required to flood the whole world to the height of Mount Everest, so I took up the challenge.
  2. Hellish exoplanet has Earth-like density and composition (Ars Technica): It’s difficult to measure both the mass and the size of exoplanets (planets orbiting other stars), because discovery methods are complementary to each other. A new pair of papers described the first exoplanet with a density similar to Earth’s, meaning it probably has a similar composition. However, the planet is hot enough to melt most rocks. Don’t plan your vacation there.
  3. New LUX experiment: No dark matter in this corner (Ars Technica): Researchers operating the Large Underground Xenon (LUX) dark matter detector announced the results of the first three months of operation. They found: nothing. Well, specifically they found nothing where some other detectors might have found a possible dark matter signature.
  4. Ghosts in the detector: why null results are part of science too (Galileo’s Pendulum): To follow up that previous article, here’s why the LUX detector wasn’t a failure, and definitely why we shouldn’t think dark matter doesn’t exist.
  5. A comment on comments, with cats (Galileo’s Pendulum): Comments on websites have always been a point of some debate. Do we have them? How do we moderate them? What constitutes reasonable commenting, and who makes that decision? Because of an ongoing “debate” between a few vocal people about pterosaur flight (of all things) on an old post about gravity, which I simply don’t have time or willingness to moderate, I decided to close down comment threads on older posts. That riled some people up.
  6. So close, yet so far (Galileo’s Pendulum): The closest star to the Solar System is invisible to the unaided eye, but in many ways it’s a more typical star than the Sun — much less the other stars we see in the night sky.
  7. The census of alien worlds (Galileo’s Pendulum): The Kepler observatory’s primary mission is over, but its legacy lives on. Based on Kepler data, scientists have estimated the possible number of Earth-class planets orbiting at habitable distances from Sun-like stars. Here’s my take on that study.
  8. I don’t believe in science (Galileo’s Pendulum): Oftentimes, big ideas in science — the Big Bang model, evolution, climate change — are regarded as optional, matters of belief. Here are some of my musings about science, belief, and what it means to trust science in the face of bad behavior, fraud, and controversy.
  9. Weekly Space Hangout (Universe Today): Yesterday, I participated in the weekly round-up of space and astronomy news, in conversation with other science writers. Much fun was had!