It seems to me…
“Ground Control to Major Tom
Commencing countdown, engines on
Check ignition and may God’s love be with you.” ~ Major Tom[i] – 1969, (David Bowie).
Last week, atmospheric carbon dioxide (CO2) was measured at over 400 parts per million (ppm) at the monitoring station in Hawaii which sets the global benchmark. The last time worldwide carbon levels probably were that high was at least 2 million years ago[ii].
In other supposedly unrelated news last week, it was announced by the nonprofit organization Mars One that over 78,000 people have applied to become Red Planet colonists since their application process opened on April 22[iii]. Maybe those applicants have considered the probable results of continued global warming and think their possibilities seem better somewhere other than on Earth.
While 400ppm only has significance as a convenient round number, had been anticipated, and will not result in any obvious environmental impact, it still marks a milestone indicating global warming continues to increase out of control. Emissions have exceeded the point at which the Earth’s natural systems are able to absorb them.
There are natural fluctuations of greenhouse gas from volcanoes and decomposing plants and animals. Over the last 800,000 years, CO2 levels have been between about 180 ppm during ice ages and 280 ppm during interglacial warm periods. Scientists say it may even have been 10 million years ago since atmosphere carbon dioxide was last this high. To put this in perspective, the first modern humans appeared in Africa only about 200,000 years ago.
The last time atmospheric CO2 levels exceeded 400 ppm, there were camels and forests in the Arctic, the tropics were locked in a near constant el Nino (the pattern that typically floods the western U.S.), and large expanses of the U.S. East Coast, Florida, and the Gulf States were underwater since sea levels were around 100 feet higher than they are today.
Simulation models predicting exactly how long will be required for sufficient ice to melt to raise global sea levels to those levels are still being refined[iv]. What is known is that CO2 levels higher that 400 ppm will result in increased heat waves, deep droughts, torrential rains, and a generally less-predictable world of weather-related events of which melting Arctic sea ice and rising sea level are only some of the obvious examples of what can be expected.
While current CO2 levels are highly problematic, the primary concern is that today’s rate of increase is more than 100 times faster than the increase following the end of the last ice age. If carbon dioxide levels go up 100 parts per million over thousands or millions of years, plants and animals can adapt but are unable to do so at current rates.
What already can be attributed to rising global temperatures is increased average global precipitation (rain and snowfall), the melting of mountain glaciers and ice sheets covering West Antarctica, Greenland, and the Arctic, and the reduction in numbers of polar bears and Adélie penguins (from 32,000 to 11,000 breeding pairs in 30 years). Some species of butterflies, foxes, and alpine plants have moved farther north or to higher, cooler areas. Spruce bark beetles have chewed up 4 million acres of Alaskan spruce trees.
Unless these trends are reversed, sea levels can be expected to rise between 7 and 23 inches (18 and 59 centimeters) by the end of the century, stronger hurricanes and other storms, and both floods and droughts to become more common. Ecosystem changes will result in some species moving farther north or become more successful while others unable to move becoming extinct. Diseases such as mosquito-borne malaria will spread northward. Some dependent species will become unsynchronized, such as plants blooming earlier than when their pollinating insects become active or the spring arrival of migratory birds arriving later than the emergence of destructive insects.
An ocean surface level increase of 3 feet would submerge considerable sections of low-lying or coastal communities and facilities along the U.S. eastern seaboard necessitating expensive relocation of power stations, refineries, hospitals, homes, etc. As warmer air holds more water vapor, inland areas can anticipate increased rainfall and flooding.
Melting ice caps, composed of fresh water, will unbalance the global ecosystem. Gulf current desalinization impact could disrupt global currents cooling Northeast America and Western Europe.
Rising oceans temperatures increase the probability of extreme weather including devastating storms. The destructive power of hurricanes has increased by 50 percent in the last 30 years.
Ocean warming has reduced phytoplankton, the tiny plants that are an integral food source for ocean life and responsible for around half of the world’s photosynthetic activity. Phytoplankton are the lowest level of the oceanic food chain so any reduction affects the entire food chain – particularly predators at the top. Ocean acidification and warmer surface temperatures increase the dangers to many aquatic animals, particularly crustaceans, mollusks, and coral reefs.
Conversely, while some areas of the planet can anticipated higher levels of precipitation, other less humid areas currently susceptible to wildfires can expect them to become more prevalent and destructive. Increased evapotranspiration and the accompanying decrease in rainfall in already semi-arid and sub-humid areas would result in desertification negatively affecting biodiversity and have a major impact on local human culture and wildlife. Droughts and heat waves could threaten food supplies.
Many heavily populated places throughout the world could become uninhabitable due to heat or other factors displacing millions of people. Resource reductions will lead to migration and population relocations resulting in social and economic impact as countries and factions seek to control valuable and dwindling resources to provide safety and shelter for their own people. Unwelcome refugees might be forced into semi-permanent camps[v].
Along with vehicular fumes, ground-level ozone, airborne industrial pollution, and stagnant hot air associated with warmer temperatures, smog represents an immediate and chronic health threat to those living in developed urban areas resulting in an increase in smog-related deaths of about 4.5 percent from the 1990s to the 2050s[vi]. Temperature increases also aggravate pre-existing respiratory system health conditions such as emphysema, bronchitis, and asthma and in general impedes the immune system’s ability to fight against infection and disease.
A so-called “Deadly Dozen” group of diseases including Avian Flu, Cholera, Plague, Ebola, and Tuberculosis are likely to spread due to global warming. Other sources of serious illnesses are aggravated by the effects of pollution and release of CFCs that harm the ozone layer. Since disease-bearing insects such as mosquitoes multiply more rapidly as temperature increases, diseases like Malaria, West Nile virus, and Dengue fever also are expected to spread. Increases in affected populations could potentially overwhelm public health services especially in poor or unprepared countries.
While it already is too late to escape much of the anticipated impact of global warming, if we hope to limit global warming to moderate or tolerable amounts, the entire world must act quickly to reduce these emissions. Otherwise all of us might consider applying to be colonists on Mars.
That’s what I think, what about you?
[ii] Tans, Pieter. National Oceanic and Atmospheric Administration.
[iii] 78,000 apply for private Mars colony project, http://www.cbsnews.com/8301-205_162-57583424/78000-apply-for-private-mars-colony-project-in-two-weeks/.
[iv] With the ice caps gone, global warming could accelerate more than rapidly than predicted. Ice caps, being white, reflect sunlight back into space cooling Earth. If the ice caps melt, the only reflector is the darker colored ocean that absorbs sunlight further warming Earth.
[v] It is estimated that the population of Mumbai will increased by an additional 7 million people by the year 2050 as global warming renders villages and hamlets uninhabitable or unprofitable, either through flooding or drought. Increased pollution would inevitable result from changes in habitation and available resources.
[vi] Result of studies undertaken by Columbia and Johns Hopkins universities.