The planet passed a milestone by mid-May of 2013 – the atmosphere hit 400 PPM Carbon dioxide. The carbon comes from both natural and human caused sources. Decomposing plant matter releases carbon naturally whereas burning fossil fuels does so “unnaturally”. Plants remove carbon during the growing season, so there is a cyclic annual variation in total carbon in the atmosphere.
For hundreds of thousands of years there was a balance between winter releases and summer decreases. Beginning in the industrial revolution of the late 18th century, winter releases have exceeded summer decreases such that the average concentration has gone from about 280 to 400 PPM.
We have a new milestone this year. This year the winter release in the northern hemisphere reached 400 PPM, almost two months earlier than last year, March 12th to be exact. This is yet another measure of the accelerating pace of the change to the atmosphere.
Some who confuse weather with climate may claim that polar vortex indicates that global warming isn’t happening, but this is a weather phenomena that was peculiar to the eastern United States. California and much of the west coast saw exceptional drought and warmer than normal weather. The iconic Iditarod sled dog race from Anchorage to Nome was hampered this year by warm weather. Portions of the 1000 mile long course were free of snow and ice.
Global climate computer models and recent observations show that the northern reaches of the planet are warming faster than areas closer to the equator. This can actually accelerate global warming due to certain feedback effects on the concentration of gases in the atmosphere.
The tundra is characterized as a treeless area where the subsurface soil remains frozen year round. During the brief summer the surface snow melts and grass and sedge grow. One might think that warmer weather and shorter periods of snow cover would be good for growth but in fact recent research suggest just the opposite. It appears that earlier snow melt and warming in the permafrost results in lower soil moisture and hence less photosynthetic productivity.
The warming in the arctic has other scary possibilities. Occasionally, reasonably well preserved but definitely dead whole animals have been recovered in the tundra. Scientists went searching for for smaller game and found a virus. The virus was found in tundra frozen for at least 30,000 years. The difference besides size is the fact the the virus was viable. The virus when thawed out was able to infect and kill amoeba.
The thawing of the tundra and its disruption by extractive industries stands a good chance of exposing animate life on this planet to disease vectors not seen for thousands of years or even never before seen. As just one example consider that smallpox, exterminated from the surface of the planet, could make a comeback. Some experts say that over the centuries it has killed more people than all other infectious diseases combined. The future is ours to protect or ruin.