Wednesday, July 22, 2015


Our planet is a tremendously complex set of systems that is very confusing to the average citizen.  To make it simpler to understand the current state of the overall global environment, posts about the latest science found on reputable sites are listed below for each of the nine planetary systems identified in 2010 by the Stockholm Resilience Centre. 

After each category title is a brief explanation of the system as written by the Stockholm Centre.  The stories posted are based on hard, vetted science - not someone's personal opinion.  To be considered vetted, the story is evaluated by qualified scientists to ensure that correct scientific procedures have been followed and that all and any data is included whether or not it supports the study's conclusions.

The systems that scientists agree have deteriorated to or beyond a practical tipping point based on the latest science are highlighted in red.  

      The Sixth Extinction:
      An Unnatural History
      by Elizabeth Kolbert
      Click to order
    • Change in biosphere integrity (biodiversity loss and species extinction)
  • Biogeochemical flows (phosphorus and nitrogen cycles)
    • The biogeochemical cycles of nitrogen and phosphorus have been radically changed by humans as a result of many industrial and agricultural processes. Nitrogen and phosphorus are both essential elements for plant growth, so fertilizer production and application is the main concern. Much of this new reactive nitrogen is emitted to the atmosphere in various forms rather than taken up by crops. When it is rained out, it pollutes waterways and coastal zones or accumulates in the terrestrial biosphere. Similarly, a relatively small proportion of phosphorus fertilizers applied to food production systems is taken up by plants; much of the phosphorus mobilized by humans also ends up in aquatic systems. These can become oxygen-starved as bacteria consume the blooms of algae that grow in response to the high nutrient supply. A significant fraction of the applied nitrogen and phosphorus makes its way to the sea, and can push marine and aquatic systems across ecological thresholds of their own.  One regional-scale example of this effect is the decline in the shrimp catch in the Gulf of Mexico's 'dead zone' caused by fertilizer transported in rivers from the US Midwest.
  • Atmospheric aerosol loading (microscopic particles in the atmosphere that affect climate and living organisms)
    • An atmospheric aerosol planetary boundary was proposed primarily because of the influence of aerosols on Earth's climate system. 
      • Aerosols play a critically important role in the hydrological cycle affecting cloud formation and global-scale and regional patterns of atmospheric circulation, such as the monsoon systems in tropical regions.
      • Aerosols have a direct effect on climate, by changing how much solar radiation is reflected or absorbed in the atmosphere. Shifts in climate regimes and monsoon systems have already been seen in highly polluted environments, giving a quantifiable regional measure for an aerosol boundary. 
      • Aerosols have adverse effects on many living organisms. Inhaling highly polluted air causes roughly 800,000 people to die prematurely each year. 
      • No limits to human effects on clouds
      • Climate change scientists must turn their attention to clean skies, experts urge
  • Introduction of novel entities (e.g. organic pollutants, radioactive materials, nanomaterials, and micro-plastics). 
    • Emissions of toxic and long-lived substances such as synthetic organic pollutants, heavy metal compounds and radioactive materials represent some of the key human-driven changes to the planetary environment. These compounds can have potentially irreversible effects on living organisms and on the physical environment. Even when the uptake and bioaccumulation of chemical pollution is at sub-lethal levels for organisms, the effects of reduced fertility and the potential of permanent genetic damage can have severe effects on ecosystems far removed from the source of the pollution. For example, persistent organic compounds have caused dramatic reductions in bird populations and impaired reproduction and development in marine mammals. 

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