By Glen Spain - Pacific Coast Federation of Fishermen’s Associations, January 2012
Its now time — perhaps long past time — for the world’s fishing industry to collectively take a firm stand against the economic and societal forces creating global warming and its related marine hazard of ocean acidification.
Both of these new phenomenon — rapidly changing climates and more acidic oceans — are expected to hit the world’s fishing industry especially hard. Indeed, they already are starting to do so. A collective response from our industry is much overdue.
What Causes Climate Change?
There is no mystery about how global warming actually works. In fact, it can be easily demonstrated in a high school science lab.
Certain naturally occurring atmospheric gases, including carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) naturally trap heat from the sun near the Earth’s surface, helping to keep our climate hospitable to life. Without that “greenhouse effect” the Earth would be nearly as cold on its surface as the planet Mars, and we would be in a permanent Ice Age.
But when normal background concentrations of these “greenhouse gases” are greatly added to by human sources such as we see today, their natural balance gets out of whack as a result, they can trap too much heat — and over time, since this heating is cumulative, this can change the balance of the whole world’s climate in unpredictable ways.
This is precisely what has been happening since the widespread use of carbon-based fossil fuels such as petroleum and coal. This huge ancient carbon sink, long stored harmlessly in the Earth, is today being rapidly burned for energy — and its fossil carbon pumped into our Earth’s atmosphere at an increasing rate. Nearly all this excess carbon dioxide can be traced by its isotopic fingerprints right back to the burning of fossil fuels.
What this global “greenhouse heating” leads to in the long-term, in addition to the heating itself, is the heat-driven disruption of normal weather patterns. Even small net heating changes in the atmosphere can lead to extreme weather disasters.
In some places this weather disruption means excessive and more frequent widespread flooding. In other places this can mean long-term or near permanent droughts in places which rarely experienced such problems in the past. In yet other places, bitter cold waves can last far longer than in the past. This plays hell with key agricultural areas all around the world.
This is why this phenomenon is more correctly called “climate change” rather than just “climate warming.” Some places will warm, others will cool, others will dry out — and most of these changes will occur in the future around statistical “means” that are quite a bit different than what these regions normally experienced in the past. When the annual weather pattern statistical “mean” changes, this is a change in climate itself. Weather is what happens in the single instance or year — climate is what happens statistically most often, described by “mean,” over many years.
Severe Weather Links Are Becoming Plainer: And the linkage between these global heating mechanisms and disastrous droughts, floods, severe weather events and climate extremes is also becoming much clearer, and much easier to statistically distinguish from normal ranges of variation in the past. These last two years, 2010 and 2011, have seen record-breaking extreme weather events worldwide, costing many billions of dollars in economic damages from record floods and droughts, tornadoes and hurricanes, including massive crop failures in many areas. Not surprisingly, 9 out of the world’s 10 hottest years on record have occurred since 2001, and all 12 of the world’s hottest years on record since 1997.
Worse, global CO2 emissions in 2010 were recorded by the World Meteorological Organization (WMO) (www.wmo.int, Press Release No. 934) to have jumped upwards by the highest one-year rate ever recorded — about 1.4 percent — since 2009. Record rates of increase also includes two other greenhouse gases — methane (CH4) and nitrous oxide (N2O), both of which are even more powerful greenhouse gases than CO2, but typically occur at much lower concentrations. Yet even small additional inputs of these more powerful non-carbon greenhouse gases can have exacerbating effects on climate.
But CO2 still accounts for about 80 percent of all observed atmospheric warming. CO2 is also the only major greenhouse gas we humans can do much about, which is why the focus is on this gas and not the others.