How Urgent is Climate Change?

April 6, 2019


  • There are short term problems. For example, ocean acidification and coral bleaching. Heat waves, reductions in agricultural production, increase in forest fires due to drier, hotter and more extreme weather conditions. Most of California’s largest wildfires have occurred within the past 30 years.
  • Since the Industrial Revolution, atmospheric CO2 has increased from 280 to 409.36 parts per million (ppm). 409.36 ppm is higher than CO2 has been in millions of years. CO2 is rising by 2 ppm per year as we continue to burn fossil fuels. To stabilise the Earth’s climate, we must reduce CO2 to the relatively safe level of 350 ppm.

  • The global climate has warmed only 0.7°C, but has not yet fully responded to our past emissions. If CO2 remains at 390 ppm long enough for the ice sheet feedback to kick in, the delayed warming would eventually reach 2°C. Right now we stand at an intersection. What we do in this decade is crucial. If we choose one path, by the end of the decade the world could be well on its way to phasing out coal. If we choose the other, we face an uncertain future in which the only certainty is a continually shifting climate.
  • “Present policies, with continued construction of coal-fired power plants without CO2 capture, suggest that decision-makers do not appreciate the gravity of the situation. We must begin to move now toward the era beyond fossil fuels… The most difficult task, phase-out over the next 20-25 years of coal use that does not capture CO2, is Herculean, yet feasible when compared with the efforts that went into World War II. The stakes, for all life on the planet, surpassing those of any previous crisis. The greatest danger is continued ignorance and denial, which could make tragic consequences unavoidable.”
  • If we stopped emitting new CO2 today, and held existing concentrations constant, we would see the earth continue to warm up in quite some time.  With business as usual, we will see accelerating CO2 emissions causing deteriorating climate, and we will also see deteriorating climate as the Earth tries to reach equilibrium with the CO2 already emitted.  Both of these will mean that Miami will be flooded sooner (50 years) rather than later (100 years), plus we will have less time to react.
  • According to greenhouse theory, throughout the ages Earth should have been exceedingly hot. Instead, global temperatures were no warmer than today. Clearly, other factors besides atmospheric carbon influence Earth temperatures and global warming.  
  • While we may not yet have reached the “point of no return”—when no amount of cutbacks on greenhouse gas emissions will save us from potentially catastrophic global warming—climate scientists warn we may be getting awfully close. Since the dawn of the Industrial Revolution a century ago, the average global temperature has risen some 1.6 degrees Fahrenheit. Most climatologists agree that, while the warming to date is already causing environmental problems, another 0.4 degree Fahrenheit rise in temperature, representing a global average atmospheric concentration of carbon dioxide (CO2) of 450 parts per million (ppm), could set in motion unprecedented changes in global climate and a significant increase in the severity of natural disasters—and as such could represent the dreaded point of no return.