Click on xkcd for more from Randall Munroe. Hat tip to kottke.org.
Archive for the ‘Science’ Category
What the ETs are hearing from us
June 5, 2013Beauty in the eye of a physicist
May 26, 2013This video is based on a 1981 interview with the late Richard Feynman, responding to those who say that scientific knowledge destroys poetic appreciation of beauty.
The greenhouse effect is a planetary problem
May 8, 2013Greenhouse gas emissions are an international problem, not just a U.S. problem, as my friend Richard Brown pointed out and as the charts below show.
China has overtaken the United States as the largest producer of greenhouse gasses overall. But the United States is still a leader among the world’s major industrial nations in greenhouse gas emissions per person.
This is a difficult problem for which I don’t see a good answer. Obviously it is no solution if one nation reduces its greenhouse gas emissions and all the rest keep pumping more carbon into the atmosphere. But if every nation waits for all the others to go first, then nothing will happen until global warming becomes unendurable.
A partial answer is that there are a lot of things that will help alleviate global warming that are good in and of themselves—increasing energy efficiency, reducing air pollution, eliminating waste, developing renewable sources of energy.
The situation is ever-changing, and some of this information may be out of date. Germany once set an example to the world in renewable energy, but reportedly is shifting to increased use of coal and hydraulic fracturing for natural gas. I don’t think the United States is the only bad nation in the world, but I do think we Americans have a responsibility to get our own house in order if we intend to lecture other nations on their responsibilities.
Experimenting with the planet Earth
May 7, 2013We’re now in the midst of an experiment whose subjects are everyone who lives on the surface of the planet Earth.
The experiment is to determine how much greenhouse gasses can be injected into the atmosphere without reaching a tipping point of irreversible global warming.
We know that methane, carbon dioxide and other greenhouse gasses trap the reflected heat of the sun and make the Earth warmer than it otherwise would be. Without this greenhouse effect, we’d be living in an ice age. The concentration of carbon dioxide in the atmosphere was 275 parts per million 200 or so years ago, when the industrial revolution was in its infancy. The concentration is steadily rising and will soon reach 400 parts per million. Some climate scientists say that it would be catastrophic to let the concentration get above 450 ppm; others say we need to get it down to 350 ppm.
I don’t know who is right, but it would be too bad to find out the hard way. The only things of which we can be sure is (1) there is some concentration that will be a catastrophic tipping point and (2) if the concentration of carbon dioxide and other greenhouse gasses continues to increase, we will reach that tipping point, whatever it is.
Click on 400ppm: A Tree Falling in the Forest | 400 Parts Per Million for more about the 400 parts per million milestone (and a hat tip for the chart).
Click on The Science of 350, the Most Important Number on the Planet for an essay by environmental writer Bill McKibben.
Click on The ‘Climate Change Debate’ Is Science Versus Snake Oil for a list of organizations that accept the reality of global climate change and a list of those that question it.
Now it is true that evidence suggests that, in past geologic ages, the carbon dioxide concentrations were greater and the temperature of the Earth was a lot hotter than it is now. The evidence also suggests that sea levels were 75 feet higher than they are now. This would be another interesting experiment—to see how extreme conditions can be without crashing civilization.
The most astounding fact about the universe
May 5, 2013The most astounding fact about the universe, according to astrophysicist Neil deGrasse Tyson, is that the atoms that make our bodies, whose complexity makes life possible, were forged in the crucibles of stars. Nuclear fusion in stars is responsible for the creation of carbon, oxygen, nitrogen, calcium, iron and all the other substances that make up our bodies. Everything is connected. Or, as we Unitarian Universalists like to put it, we must respect the interdependent web of all existence of which we are a part.
The video below tells how the elements of life are forged.
Hat tip to notes to ponder.
Evidence that global warming is human-made
May 3, 2013The reason to think that global climate change is caused by human activity is that human civilization increases the amount of greenhouse gasses, such as methane and carbon dioxide, that are known to trap the heat of the sun as it is reflected in infra-red rays. Never before have greenhouse gasses increased as so rapid a rate, and never before, so far as is known, have average global temperatures increased at so rapid a rate. The world has been hotter in the past than it is now, but the evidence from tree rings and glacial cores is that the change has never been as rapid as it is now.
If there is another cause, it is not known, and greenhouse gasses make it worse.
Click on the following links for more
How do we know global warming is human-caused?
Hockey Stick Graph Now Even More Stickish
The Scariest Climate Change Graph Just Got Scarier
Large rise in CO2 emissions sounds global climate change alarm
Confirmation that global warming is real
May 3, 2013
The chart is based on the World Meteorological Organization’s report for 2012. El Nino is a cyclical weather phenomenon in which warm water is brought to the surface of the Pacific Ocean. La Nina is an opposite cyclical phenomenon in which cold water is brought to the Pacific surface.
I always had trouble accepting that it was possible to measure average global temperatures so accurately that you could measure variations of less than 1 degree, or that such variations mattered. But as the chart below shows, a small change as measured on the thermometer has a big effect.
This chart shows Arctic sea ice on Sept. 16 of last year, when the Arctic ice cap had shrunk to the smallest extent on record, compared with the average annual minimums during the past 30 years (indicated by the yellow line).
Click on UN Warns of ‘Worrisome’ and ‘Disturbing’ Signs of Climate Change for more.
Click on El Nino and La Nina: Weather’s Sibling Rivalry for explanations of these weather patterns.
Why save a world that’s going to end soon?
May 3, 2013My friend Bill Elwell called my attention to this article on The Raw Story web site.
The United States has failed to take action to mitigate climate change thanks in part to the large number of religious Americans who believe the world has a set expiration date.
Research by David C. Barker of the University of Pittsburgh and David H. Bearce of the University of Colorado uncovered that belief in the biblical end-times was a motivating factor behind resistance to curbing climate change.
“[T]he fact that such an overwhelming percentage of Republican citizens profess a belief in the Second Coming (76 percent in 2006, according to our sample) suggests that governmental attempts to curb greenhouse emissions would encounter stiff resistance even if every Democrat in the country wanted to curb them,” Barker and Bearce wrote in their study, which will be published in the June issue of Political Science Quarterly.
The study, based on data from the 2007 Cooperative Congressional Election Study, uncovered that belief in the “Second Coming” of Jesus reduced the probability of strongly supporting government action on climate change by 12 percent when controlling for a number of demographic and cultural factors. When the effects of party affiliation, political ideology, and media distrust were removed from the analysis, the belief in the “Second Coming” increased this effect by almost 20 percent.
“[I]t stands to reason that most nonbelievers would support preserving the Earth for future generations, but that end-times believers would rationally perceive such efforts to be ultimately futile, and hence ill-advised,” Barker and Bearce explained.
That very sentiment has been expressed by federal legislators. Rep. John Shimkus (R-IL) said in 2010 that he opposed action on climate change because “the Earth will end only when God declares it to be over.” He is the chairman of the Subcommittee on Environment and the Economy.
Though the two researchers cautioned their study was not intended to predict future policy outcomes, they said their study suggested it was unlikely the United States would take action on climate change while so many Americans, particularly Republicans, believed in the coming end-times.
“That is, because of institutions such as the Electoral College, the winner-take-all representation mechanism, and the Senate filibuster, as well as the geographic distribution of partisanship to modern partisan polarization, minority interests often successfully block majority preferences,” Barker and Bearce wrote. “Thus, even if the median voter supports policies designed to slow global warming, legislation to effect such change could find itself dead on arrival if the median Republican voter strongly resists public policy environmentalism at least in part because of end-times beliefs.”
via The Raw Story.
Looking at the sun
April 28, 2013The video shows three years of time lapse photos of the Sun, taken at the rate of two a day by NASA’s Solar Dynamics Observatory, at a time in the solar flare cycle when flare activity is at its height.
In this video, the Sun looks like it is alive. But the apparent pulsation is due to variations in the position of the SDO as it orbits the Earth while the Earth orbits the Sun. Each of the flickers is a solar flare discharging orders of magnitude more energy than all the atomic bomb explosions in history.
Click on NASA – Three Years of SDO Images for background.
Hat tip to kottke.org.
The hierarchies of knowledge
April 11, 2013I lifted these two cartoons from the Biology vs. Theoretical Physics post on the Sans Science web log.
The top cartoon is, of course, from Randall Munroe’s xkcd series.









