Carbon Counter Launched
A massive new billboard was installed in midtown Manhattan on June 18. It's a first-ever carbon counter that gives an up-to-the minute reading of greenhouse gases into the atmosphere. Deutsche Bank funded the enterprise, modeled on the debt clock, and said it plans to keep the counter where it is for years.
The counter factors in not only carbon dioxide, but also the other major greenhouse gases (such as methane) where humans are making important direct contributions to the atmosphere (details here). The result is one large value in carbon dioxide "equivalent" — just over 3.64 trillion metric tons at the time of the counter's launch.
So far, the planet has warmed 1.3 degrees Fahrenheit since humanity started burning large amounts of fossil fuels, such as coal, over two centuries ago. The projected total warming commitment from the carbon dioxide equivalent that has now accumulated in the atmosphere, as shown on the carbon counter, is between 2.7 and 5.9 degrees F (based on conservative estimates of likely "climate sensitivity"; see here, here, and here).
At the current rate of increase shown by the counter, the atmosphere would, before 2050, reach a level committing the planet to between 3.6 and 8.1 degrees F of warming over time (based on the same climate sensitivity research, for a doubling of carbon dioxide). Many scientists and governments look to 3.6 degrees F as a significant risk threshold for disruptive climate change.
The projections for warming here do not take into account the cooling effect of aerosols in the atmosphere, which currently diminish overall warming. Aerosols, like carbon dioxide, are added to the atmosphere mainly by burning fossil fuels. However, they remain suspended in the air only about a week, whereas carbon dioxide remains for about a century. Therefore, aerosols’ cooling effect will decrease significantly if and when nations reduce their carbon dioxide emissions to stop further buildup of carbon.