By Frank Thomas
Within three decades scientists warn, warming will be irreversible. The world’s top scientists have just formally embraced an upper limit on greenhouse gases for the first time … establishing a target level at which humanity must stop spewing them into the atmosphere or face catastrophic climate changes. Scientists warned the target was likely to be exceeded in a matter of decades unless steps were taken soon to reduce emissions. The experts cited a litany of changes already under way, warned that they were likely to accelerate and expressed virtual certainty that human activity was the main cause.
This was reported last September in the International Herald Tribune and was taken from the Intergovernmental Panel on Climate Change (IPCC) report in 2012.
One of the world’s leading climate researchers, Kevin Trenberth, head of the Climate Analysis Section at the U.S. Center for Atmosphere Research in Boulder, Colorado came up with the best single, simple explanation of climate change. His concise explanation – with which I fully agree from my ongoing examination of what’s going on with climate change – was :
The Earth is habitable because of a natural greenhouse effect brought about mainly by water vapor (60%) and carbon dioxide (26%). Otherwise, Earth’s average temperature would be below zero Fahrenheit. Humans are altering the composition of the atmosphere, mainly by fossil fuels. As a result, carbon dioxide has gone up over 35% (as of Dec. 2010 or 43% as of Dec. 2013) since pre-industrial times and over half of that is since 1970. This changes the greenhouse effect and traps radiation that would otherwise escape to space, thus producing warming. The warming is manifested in many ways, not just increasing surface temperatures, but also melting ice, and changing the hydrological cycle and thus rainfall. Since 1970, the effects are large enough to be outside the bounds of natural variability for global mean temperatures, but global warming does not mean inexorable increases in temperature year after year owing to natural variability.”
So much for the unfounded reactions of die-hard climate change skeptics who in effect say greenhouse gases (GHGs) do not impact climate volatility. The recent revelation of a 60% increase in the Arctic ice cap over the last 12 months does NOT support the deniers’ propaganda that climate change is inherently NOT human caused … that it’s a cycle and fluctuation process naturally caused which has existed for millions of years. Pure nonsense, no scientific basis whatsoever!
Pages and pages of myths have been taken down with the force of hundreds of scientific papers. Consequently, 97% of climate scientists, every major scientific body in the world and a large segment of the general public agree human GHG emissions are changing the climate. But with the exception of Germany, Denmark, Sweden, and California, global action has been tragically weak to what is globally happening.
The 259 scientists from 39 countries who drafted the 5th IPCC REPORT are more convinced than ever that global warming is “unequivocal” and humans have been the primary cause of it over the last 60 years. That the warming-up trend is human caused is now considered “extremely likely” or a 95-100% certainty, an upgrade from a “very likely” 90%-100% certainty in the 4th IPCC report.
What the authors are not so confident about is the slowdown in the rate of warming over the past decade or more – despite sharply rising carbon dioxide concentrations. The report admits this is not fully understood, but the most plausible answer is the natural variability of climate. The report concludes that the long “pause” in the rate of increase in warming – the highest average global temperature occurred 15 years ago – is partly due to changes in the system. For example, this includes a redistribution of heat within the ocean, and factors such as solar output. Also aerosols produced by volcanic eruptions can reflect radiation back into space, thus having a cooling effect.
Of course, there are some big uncertainties, e.g., the likely amount of warming at given levels of GHG emissions, how much the sea level will rise which can be quite different for Northern and Southern Hemispheres and at what point there is certainty that plants and animals will largely be exterminated. But the IPCC report is adamant in saying that even a future “warming pause” of 15 years is too short a period to make a clear judgment.
As one American scientist who participated in writing the 5th report commented, “People think that global warming means every year is going to be warmer than the year before. It doesn’t work that way. It’s more like a stair-step process.”
As stated, the temperature ups and down are short-term fluctuations, mostly reflecting natural variability within the past underlying 60-year gradual trend of warming of surface air temperatures. But despite short term fluctuations there has been an inexorable retreat of mountain glaciers and Arctic sea ice in the last 30 years. Also Arctic (and Antarctic) oscillations which intensify stratospheric wind speeds have in turn increased earth warming via a stratospheric positive feedback. Other contributive factors are an ecologically destructive deforestation on a massive scale and soaring ocean acidification that’s destroying phytoplankton that generates much of the atmosphere’s oxygen.
As the oceans absorb more anthropogenic (definition: of, relating to, or resulting from the influence of human beings on nature) CO2, this has a severe affect on coral reefs and causes coral bleaching. The present fossil fuel acidification is much faster than natural changes and so this acid spike will be more intense than the Earth has seen in the last 800,000 years as reported by the Royal Society of UK.
From my studies, it’s of course clear that natural external climate variations – like volcanic eruptions and fluctuations in solar output – play a role. For example, the mid-century 1930-40 warming was to a significant extent caused by an increase in solar radiation. The sharp, sudden short-lived drop in global surface air temperature in 1991 was caused by the Philippine volcano, Mt. Pinatubo. A well-known example of an internal natural climate variation is El Nino. Every four years this causes a warming of the Equatorial Pacific. This happened in 1997-98 and contributed significantly to making 1998 the warmest year in the world to date.
As summarized in the 5th IPCC report: because of natural changes in the climate, ‘trends’ based on short term records are very sensitive to the beginning-and-end date. They do not in general reflect long-term climate trends. The larger trend is clearly towards warming. Each of the past three decades has been warmer than all others since 1850, and the first decade of the 21st century was the warmest.
The point is that natural fluctuations have to be set aside or ignored to correctly see the human influence on climate. As one scientist noted:
Had forecasters extrapolated the mid-century warming into the future, they would have predicted far more warming than actually occurred. Likewise, the subsequent cooling trend, if used as a basis for a long-term forecast could have erroneously supported the idea of a rapidly approaching ice age. The detection of the (human determined) anthropogenic climate direction thus requires at least the analysis of long-term records. This is because we can easily be fooled by the natural fluctuations or background noise level, and we need to understand their dynamics to better estimate the internal noise level, i.e., the anthropogenic emission of GHGs (Professor of Physics Mojib Latif of Kiel University).
IPCC scientists believe Arctic summer ice has already vanished more quickly in the past 30 years than in the previous 2000 years! Also, it may vanish completely before the middle of this century. This is the long-term trend in the face of superimposed short-term climate fluctuations like the recent 2012 Arctic ice cap increase. One climate scientist says, “The GHGs in the atmosphere will continue to accumulate for years, possibly decades, which together with the climate inertia of the climate system will support further warming.”
This is another reason IPCC scientists conclude a long-term trend towards increasing anthropogenic earth warming – made worse by positive feedbacks like the Arctic Oscillation and a potentially huge methane release in the Arctic – is a not too distant reality. For example, consider global vehicle registrations, which have increased from 250 million in 1970 to 1 billion in 2010, and are forecasted to reach 2 billion by 2020. The change to electric vehicles will not diminish GHGs as long as the electrical energy to power them is produced by power plants which burn fossil fuels.
On the positive side, Nature Geoscientist published a recent study suggesting the planet may warm more slowly than feared, perhaps buying an extra decade for more aggressive near-term actions and policies to improve energy efficiency, to rigidly limit and phase out CO2 intensive coal-fired power plants, to eliminate fossil fuel subsidies and transition out of oil.
Global emissions can be slowed and reduced if we cut our GHG emissions, plant millions of trees and halt the slashing of forests, insulate homes and commercial buildings, use solar/wind for heating and cooling, use geothermal energy for vehicles, convert to bio-diverse organic agriculture, harvest phytoplankton in mass to strengthen sea-oxygen production and neutralize carbolic acid in seas. As CO2 concentrations reach 450 ppm, scientific research shows that this will result in grave harm to marine ecosystems and produce several ocean biogeochemical changes.
While a slowdown in earth warming – despite soaring CO2 emissions – may offer more time to take action on the exceptional hazards of climate change, TIME is getting TIGHTER and TIGHTER. COSTS of inaction are getting HIGHER and HIGHER. Delay will make us more dependent on vastly new technological innovations that carry the high risk of not being developed in a timely manner. We’re in an unstable climate system exposed to “forcings” from changes in solar radiation and greenhouse gases. In the words of Richard Alley, a world leading glaciologist and recognized analyst of Greenland ice cores:
“Abrupt climate change could always occur. But the existence of forcings greatly increases the number of possible mechanisms for abrupt change. And the more rapid the forcings, the more likely it is that the resulting change will be abrupt on the timescale of human economies or global ecosystems.”
Alley and most scientists agree that humanity is today pushing planetary life systems toward their limits. The “greenhouse effect” is good up to a point since without it planet Earth would be frozen. But there can be too much of a good thing. The man-made greenhouse gas effect is putting even more energy into the entire global system, and this will only increase global warming and wild weather volatility. Furthermore,this will be amplified by feedback effects. This global reach differs from natural oscillations that primarily redistribute heat.
The stakes are HIGH. Will we face the facts … or will we irresponsibly continue gambling that anthropogenic GHGs will not lead to an extensive ecological-human extinction by mid-century?
February 8, 2014, Frank Thomas, The Netherlands