The threshold of 400 carbon dioxide molecules per million molecules of Earth’s atmosphere is an arbitrary but still significant milestone, reflecting a near 50% increase in the concentration of the greenhouse gas since humanity first started burning fossil fuels for industry. Sure, the Earth has experienced hotter chemistry before, but Peter Gleick says it all the in the title of his post: The Last Time Atmospheric CO2 was at 400 parts per million Humans Didn’t Exist. The Arctic was also free of ice, and CO2 levels were changing 1000 times slower than they are today. Not that we can’t survive and even thrive in the midst of an economy that daily poisons and deadens the Earth, but it will be a much uglier place we have paid for.
Last week the European Union voted to ban neonicotinoid pesticides in an effort to fight colony collapse disorder among honeybees. Although research has clearly fingered these pesticides in bee behavioral problems, the ban is still rather speculative, as multiple environmental factors may be at play in CCD. Greg Laden writes “navigation over long distances, communicating with other bees about newly found hard to get and far away sources of food, mechanisms of controlling reproduction within the colony, thermoregulation of the hive, building and maintaining architecture,” and other bee necessities offer many points of vulnerability. Several EU member countries, including the UK, voted against the ban, resulting in a short-term imperative that Greg calls “more of a giant experiment than an actual ban.” Still, it’s a step toward understanding and alleviating the plight of one of humanity’s dearest friends.
Walking on two legs, time and space seem universal, but take a good look at the universe, and things start to get mushy. Chad Orzel defines time with a circular-sounding title, writing “there isn’t a giant master clock at the center of the universe that everybody sets their watches by.” Although time can only be measured in ticks, two clocks are seldom in agreement. Chad says “Scientists in Colorado have clocks so good they can measure the change in time from moving at walking speed, or from moving one foot higher in elevation.” On Starts With a Bang, Ethan Siegel revisits the speed of light in a vacuum, which nothing apparent can exceed. If you’re a proton instead of a photon, your speed limit is a little bit lower, thanks to interaction with the cosmic background radiation. New upgrades to the Large Hadron Collider will boost the top speed of its protons by 8 m/s, only 3 m/s short of lightspeed.