MOST PRUDENT ACTION

Though the average city slicker wouldn’t notice, global warming is melting glaciers, creating intense hurricanes, and heating up forest fires in the United States so much that more wildfires than ever are blazing more area for longer periods of time, because as earlier and earlier springs trigger earlier snow-melt, forests become drier and stay so longer.

Though the average hiker wouldn’t notice, the Alps and other mountain ranges have experienced a gradual growth spurt over the past century or so thanks to the melting of the glaciers atop them. For thousands of years, the weight of these glaciers has pushed against the Earth’s surface, causing it to depress. As the glaciers melt, this weight is lifting, and the surface slowly is springing back. Because global warming speeds up the melting of these glaciers, the mountains are rebounding faster.

Though the average astronomer wouldn’t notice, our warmer planet’s carbon dioxide emissions is having effects that reach into space with a bizarre twist. Air in the atmosphere’s outermost layer is very thin, but air molecules still create drag that slows down satellites, requiring engineers to periodically boost them back into their proper orbits. But the amount of carbon dioxide up there is increasing. And while carbon dioxide molecules in the lower atmosphere release energy as heat when they collide, thereby warming the air, the sparser molecules in the upper atmosphere collide less frequently and tend to radiate their energy away, cooling the air around them. With more carbon dioxide up there, more cooling occurs, causing the air to settle. So the atmosphere is less dense and creates less drag.

Though the average gardener wouldn’t notice, as global warming brings an earlier start to spring, the early bird might not just get the worm. It might also get its genes passed on to the next generation. Because plants bloom earlier in the year, animals that wait until their usual time to migrate might miss out on all the food. Those who can reset their internal clocks and set out earlier stand a better chance at having offspring that survive and thus pass on their genetic information, thereby ultimately changing the genetic profile of their entire population.

Though the average anthropologist wouldn’t notice, not only is the planet’s rising temperature melting massive glaciers, but it also is thawing out the layer of permanently frozen soil below the ground’s surface, with a whopping 125 lakes in the Arctic disappearing in the past few decades, backing up the idea that global warming is working fiendishly fast nearest Earth’s poles. This thawing causes the ground to shrink unevenly, and leads to sink holes and damage to structures such as railroad tracks, highways and houses. Meanwhile, the destabilizing effects of melting permafrost at high altitudes is causing rockslides and mudslides, with recent discoveries revealing the possibility of long-dormant diseases like smallpox re-emerging, as the ancient dead, their corpses thawing along with the tundra, get discovered by modern man.

Though the average botanist wouldn’t notice, the melting in the Arctic might cause problems for plants and animals at lower latitudes, but it’s creating a downright sunny situation for Arctic biota. Arctic plants usually remain trapped in ice for most of the year. Nowadays, when the ice melts earlier in the spring, the plants are eager to start growing. Research has found higher levels of the form of the photosynthesis product chlorophyll in modern soils than in ancient soils, showing a biological boom in the Arctic in recent decades.

Though the average naturalist wouldn’t notice, we’ve all had to start looking at slightly higher ground to spot our favorite chipmunks, mice and squirrels. Researchers found that many of these animals have moved to greater elevations due to changes in their habitat caused by global warming. Similar changes, of course, are also threatening Arctic species like polar bears as the sea ice they dwell on gradually melts away.  

Though the average doctor wouldn’t notice, those sneeze attacks and itchy eyes that plague us every spring have been worsening in recent years. Global warming over the past few decades has caused more and more of us to start suffering from seasonal allergies and asthma much sooner than normal. Though lifestyle changes and pollution ultimately leave people more vulnerable to the airborne allergens they breathe in, research has shown that the higher carbon dioxide levels and warmer temperatures associated with global warming are also playing a role by prodding plants to bloom earlier and with more allergens produced earlier, allergy season lasts longer. What does this all mean? Well;

1. Global warming is real. Multiple types of measurements and analyzes (weather stations, sea level monitors, borehole temperatures) agree with each other and show that the planet has warmed by 1.1 °C or 2 °F since about 1750. The magnitude of warming, and the rate of warming is beyond natural variation.

2. Warming varies with geography and with time. Climactic changes on planet Earth are not constant in time or space. High latitude regions may warm three times as much as the global average. Some regions may cool for extended periods. Short-term (annual, decadal, multi-decadal) Climactic changes are caused by sun spot cycles, El Nino/ La Nina, volcanic eruptions, and ocean current variations. These natural variations in time and space have existed in the past and should be expected in the future.

3. The global temperature record is best understood as the combination of a slow, long-term warming (un-natural/anthropogenic) and shorter-term fluctuations (natural). The combination is a record that has considerable variability: decade or more periods of temperature stagnation or decrease (1900-1910; 1945-1975) and periods of rapid increase (1910-1945; 1975-2005). The increases clearly dominate the decreases for global temperatures, producing a net warming of 0.8 °C or 1.4 °F since 1880, near the start of the instrumental record.

4. The most likely cause of 21th century long-term warming is the increase in green house gases related to human population growth and activity. This enhanced greenhouse effect should not be confused with a natural greenhouse effect caused by water vapor and background carbon dioxide in the atmosphere prior to human activity of burning hydrocarbons (Industrial Revolution). The natural greenhouse effect has prevented Earth from being an icy planet and allows the biology appropriate for a “blue planet” whose mean temperature is about 15 °C.

5. Carbon dioxide is the most important of anthropogenic greenhouse gases causing current warming. It’s prominence results from its atmospheric abundance combined with the warming potential of carbon dioxide molecules. Carbon dioxide also has a long atmospheric lifetime. If emissions of carbon dioxide were to plummet to zero today, it would take about 200 years for the Earth’s temperature to drop to pre-industrial values. The Earth (oceans, biomass) is now absorbing about half of the carbon dioxide we are putting into the atmosphere each year; the other half stays in the atmosphere, increasing the greenhouse gas concentration by about 2 parts per million per year. Our actions of today are mortgaging future generations.

6. Without immediate global action, projections to 2100 show carbon dioxide concentrations growing to about 600 parts per million, double current concentrations. Future global temperature increase for that much greenhouse forcing will be about 2.5 °C or 4.5 °F. Temperature change in the Arctic could be three times the global increase. Such temperature changes will cause sea level to rise, many glaciers to melt, snow seasons to shorten, and persistent drought. Spring runoff will be earlier, but summers will be longer and hotter. Agriculture will be disrupted. There will be both losers and winners in a warmer world; most researchers predict that losers will outnumber winners.

7. What’s the most prudent path? The most prudent action we can take, with our children and grandchildren in mind, is to curb greenhouse gas (particularly carbon dioxide) emissions immediately. There are many benefits from moving from a carbon-based economy and dependence on foreign governments, to a more sustainable green economy.

To be continued……

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