||Frequently Asked Questions about Climate Change

Prepared by Douglas Muschett, Ph.D,. a (mostly) retired researcher and consultant specializing in climate change mitigation and sustainable development. Please click highlighted links for additional resources.

Sometimes I hear people talk about “global warming”   and at other times I hear people talk about “climate change”.  Why the difference?

I also have heard that the “greenhouse effect”  causes  global  warming. How does that work?

Isn’t some carbon dioxide increase in the atmosphere and some temperature increase beneficial to life on earth?

Why is global warming so important now…haven’t we always throughout history had periods of global warming and cooling?

In what ways do human activities affect greenhouse gases in the atmosphere?

Are there other benefits from taking actions to combat global warming?

Sometimes I hear people talk about “global warming”   and at other times I hear people talk about “climate change”.  Why the difference?

Both of these terms are used correctly to describe the current situation, but there is an important difference.  Global  warming  of  the atmosphere is  the basic type of climate change, which in turn can drive other forms of climate change.  For example,  warmer  atmospheric  temperatures  can  cause increased soil  temperatures,   increased evaporation and more severe drought conditions.  Increased snowmelt and ice melt, more severe storms and floods are other types of climate change which can be caused by global warming.

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I also have heard that the “greenhouse effect”  causes  global  warming. How does that work?

The “greenhouse effect” is so named because the atmosphere replicates what happens inside a greenhouse (or a closed automobile) on a sunny day.  Short wave length solar radiation passes through the glass and warms the interior surface of the greenhouse.  The surface then gives off long-wave radiation,  but the latter cannot penetrate and is trapped inside the glass, which causes warming to take place. Similarly several “greenhouse gases” in the atmosphere,  most notably carbon dioxide and methane,  trap and prevent long-wave radiation which is emitted from the earth’s surface from escaping back into space.

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Isn’t some carbon dioxide increase in the atmosphere and some temperature increase beneficial to life on earth?

In general, the Intergovernmental Panel on Climate Change notes that some increase in the concentration of greenhouse gas carbon dioxide is beneficial towards providing additional nutrients for plant life and that small increases in temperature may reduce the incidence of frost and extend the growing season in cooler climates. (At the same time, it should be noted  that relatively small changes in the average global temperature can translate to more severe temperature increases and effects at regional levels, such as is occurring with ice melt in the arctic region.)   However, severe impacts occur when the temperature increases too much and too rapidly. Many scientists believe that when temperature increases beyond 1-3 degrees C  (2-5 degrees F) that there will increasingly negative impacts. Individual species and whole ecosystems cannot adapt quickly enough, and many species will die.  Changes in soil conditions, including erosion, and more severe droughts may cause widespread crop failures and famines,  frequently with devastation of poorer agricultural  countries.

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Why is global warming so important now…haven’t we always throughout history had periods of global warming and cooling?

Now there are six billion people dependent upon complex natural systems for survival.  As we have studied past periods of global warming and cooling, we have recognized the difficulties which species have in adapting and surviving due to both the absolute change in temperature and the rate of change. Although the global observed temperature increase during the industrial age to date seems to be a relatively modest  1 degrees F., there are already considerable impacts being observed, ranging from loss of coral reefs to desertification to loss of polar icecaps to a pine beetle epidemic here in the high country. Global climate models, based upon different assumptions and projections, suggest an average global temperature increase of 2-5 degrees C. ( 4-9 degrees F.) during the remainder of the 21st century unless strong preventive actions are taken. To make matters worse, based upon CO2  emissions data from 2008, trends indicate that recent emissions are near the top end of (previously projected)  emissions scenarios.

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In what ways do human activities affect greenhouse gases in the atmosphere?

Human activities affect the production and release of greenhouse gases in many ways.  In the United States most attention is focused upon the burning of fossil fuels, which are widely used by households, manufacturing processes, transportation activities, commercial and institutional buildings and in the generation of electricity.  Other human activities, such as construction (e.g. production of brick and cement) and agriculture indirectly cause greenhouse gas emissions.   Garbage disposal, through organic matter that winds up in landfills, produces methane,  a highly potent greenhouse gas.  Other materials, including plastics, metals and glass, when they are recycled will reduce the energy input and greenhouse gases resulting from their production.  For all of these reasons, the consumer recycling and composting programs operated by Summit County and HC3 are important means to reduce greenhouse gas emissions.

Other important human activities which contribute to global warming have not received as much attention.  Land use conversion, including deforestation and agriculture, are estimated to cause 20-25% of the greenhouse gas increase, both through the release of gases into the atmosphere and from the destruction of “sinks” which remove carbon dioxide from the atmosphere.  Some specific examples include the conversion of forest land (a “sink”) to agricultural land (which may release nitrogen gases), the conversion of forest land to suburban land uses, the raising of livestock (which release methane gases) and the cultivation of rice (which releases methane).

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Are there other benefits from taking actions to combat global warming?

One intelligent and environmentally-concerned person we know is unsure about the complicated climate change science and whether it has been conclusively demonstrated whether humans are responsible for global warming and climate change.  Nevertheless, he has chosen to act as an energy and environmental steward in his personal conduct.  Not only is he exercising the “precautionary principle” which states that in the event of uncertainty that humans should act to minimize potential catastrophic damage, but he is also helping both himself and our society to realize many other benefits from his actions.

The first and most obvious benefit to most people is saving money.  For typical households it is feasible to reduce residential fuel use, electricity consumption and gasoline use by 25%..or more. In some cases a significant investment is required,  which is then regained by the consumer over time.  After conserving energy, additional reductions in fossil fuel consumption are possible by substituting renewable forms of energy, such as wind, solar, biomass and geothermal.  (See HC3 website Energy section  for further information about  energy conservation, renewable, and available grants and financing).  In addition,  energy conservation and the substitution of renewable  energy offer many other “cobenefits”  for society.

Many federal and state and local programs have been established to solve a variety of “air pollution” problems, such as  airborne pollutants affecting human health, automobile smog, acid precipitation and even indoor air quality. However,  these are mostly “energy problems”,  which are caused by the way we use fossil fuel energy.  Hence several air pollution problems could be mostly solved through reliance upon energy conservation and renewable energy.

Moreover,  there can be a number of other economic benefits  to society.  Energy conservation and  renewable energy production are labor-intensive and can provide many new jobs in the manufacturing of insulation, metals, glass, and components, and in design, assembly and installation of energy applications;  much of the economic impact is in state and local economies. To the extent that foreign oil consumption can be reduced, the pressure to conduct expensive and tragic foreign wars will be reduced and our national security will also be enhanced.

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