NEW! Tabbed Pages for links to video tutorials, and a linked list of post titles grouped by topic.

This blog is expressly directed to readers who do not have strong training or backgrounds in science, with the intent of helping them grasp the underpinnings of this important issue. I'm going to present an ongoing series of posts that will develop various aspects of the science of global warming, its causes and possible methods for minimizing its advance and overcoming at least partially its detrimental effects.

Each post will begin with a capsule summary. It will then proceed with captioned sections to amplify and justify the statements and conclusions of the summary. I'll present images and tables where helpful to develop a point, since "a picture is worth a thousand words".

Monday, March 30, 2015

Why Care About Global Warming? “No Man Is An Island”



Global warming has been proceeding for more than a century as the result of humanity's use of fossil fuels to provide the energy that powers our economy. The excessive, rapid warming we are currently experiencing produces harms and damages from extremes in weather and climate. These include heavy rainfall and flooding, heat waves and drought, rising sea levels, and secondary health problems.

Global climate models that successfully reproduce past climate patterns are used to project future behavior of Earth's climate. They show that without significant measures taken to abate further emissions of greenhouse gases warming will continue and indeed will even accelerate, bringing more intense and more extensive extreme events that have the potential to disrupt humanity's socioeconomic well-being.

In 1624 John Donne wrote a poetic meditation, “No Man Is An Island:

No man is an island entire of itself; every man
is a piece of the continent, a part of the main;
..........................................
... any man's death diminishes me,
because I am involved in mankind.
And therefore never send to know for whom
the bell tolls; it tolls for thee.”
John Donne's brief meditation encapsulates much of the moral force underlying our need to act against further warming of the planet. If I have engaged in an act that harms a neighbor whom I know, the moral force of that wrong is evident, since my neighbor's loss reflects directly back on my deed. If instead I carry out a deceit having a negative impact on society more generally (such as bribing an official for preferential treatment, to the disadvantage of others whom I do not know) the losses of my fellow citizens resulting from the bribe similarly“diminish[] me because I am involved in mankind”, in Donne's words.

The global warming problem negatively affects humans generally. Although greenhouse gases such as carbon dioxide (CO2) are generated locally, once emitted into the atmosphere they mix with the air and contribute to warming of the atmosphere all around world. In this way my localized use of the energy derived from fossil fuels affects my fellow human beings the world over, because the excess CO2 leads to harms and damages affecting everyone. In Donne's view, the harms to others whom I do not know, but for which I am responsible, diminishes me.

Speaking in general terms, we in the developed countries of the world have powered our growth using fossil fuels for more than a century, and have been emitting the waste gas, CO2, over all that time. We continue to do so even now. Developing countries, on the other hand, are striving to attain the level of development that the developed world has already achieved; they are expanding their rates of emissions year by year. Between them, both groups of nations are responsible for most emissions released worldwide.

None of the world's peoples is immune from the harms inflicted by today's additions of greenhouse gases to the atmosphere; people in developed, developing and impoverished countries of the world, as well as in island nations, are all variously susceptible to harms from extremes of drought, flooding, or rising seas. Their losses diminish us all.

Global warming and its harms extend not only to our fellow human beings alive today, but to future generations as well. U.S. President Barack Obama, in his State of the Union address on January 28, 2014, stated a most profound and basic motivation for attacking the problem of global warming:

Climate change is a fact. And when our children’s children look us in the eye and ask if we did all we could to leave them a safer, more stable world, with new sources of energy, I want us to be able to say yes, we did.”

This statement illuminates a basic human motivation for dealing with global warming, namely, the strong desire we all feel to pass on to our children and further progeny a secure world not threatened by the consequences of our present environmental actions.

A major fraction of the CO2 emitted into the air remains there indefinitely. It persists in the atmosphere for several centuries or even longer, i.e., for many human generations. There are no natural processes that remove the excess CO2 from the atmosphere at the same rapid rate that we are adding it. Furthermore, to date no technology has been developed that could capture and store the excess CO2 on the scale needed, preventing further accumulation. As a consequence the excess CO2 we emit each year is added to the amount already present, accumulating to higher and higher levels.

Climate modeling concludes that, to a very good approximation, the increase in global average temperature is directly related to (i.e. linearly dependent on) the total accumulated CO2 in the atmosphere. Since we can't remove CO2 from the air we can never return to the lower temperatures that prevailed at earlier times, say, 20 or 40 years ago. In fact, if we humans continue emitting CO2 and other greenhouse gases, temperatures are projected to continue increasing, bringing ever more pronounced weather and climate extremes with them. Only by bringing annual emission rates to near zero as early as practically possible can we minimize further accumulation of CO2 and stabilize it at a new, higher level whose increase will be kept as low as possible. Only in this way can we stabilize the extent of additional global warming at as low an increase as possible.

By continuing to produce emissions of CO2 and other long-lived greenhouse gases, we humans are determining not only our own climatic fate, but also that of our children whom we know and love, of our grandchildren whom we prize and adore, and most importantly of our distant progeny whom we can not know. Extending John Donne's evocative phrasing, the harms we are inflicting on future generations that are beyond our ability personally to know still “diminishes [us],/because [we are] involved in [future generations of] mankind”. The peoples of the world and their elected representatives must coalesce around comprehensive, effective policies to minimize further accumulation of greenhouse gases and control the worsening of extreme weather and climate. In the absence of success in this challenging endeavor we need not “send to know for whom/the bell tolls; it tolls for [us].”

© 2015 Henry Auer