Environmental Engineering Reference
In-Depth Information
Giventhatourstandardishumanlife—wewanttheclimateweliveintobeaslivableaspossible—there
are two types of impacts we need to study and weigh. The first is the impact of CO
2
on climate itself. CO
2
affects climate in at least two ways: as a greenhouse gas with a warming impact, but also as plant food
with a fertilizing impact (plants are a major part of the climate system as well as a benefit of a livable
climate). I'll refer to these as the greenhouse effect and the fertilizer effect. The second impact of CO
2
,
which is rarely mentioned, is the tendency of cheap, plentiful, reliable energy from fossil fuels to amplify
our
ability to adapt to climate
—to maximize the benefits we get from good weather and ample rainfall and
minimize the risks from heat waves, cold snaps, and droughts. I'll refer to this as the energy effect.
Discussion of climate change often assumes that any man-made climate change is large if not cata-
strophic and that our ability to adapt is not all that important. This is unacceptable. It is prejudicial to as-
sume that anything is big or small, positive or negative, before we see the evidence. We have to actually
investigate the facts. It might be that the greenhouse effect leads to a tiny, beneficial amount of warming or
that having or not having fossil fuels to build sturdy infrastructure is the difference between two hundred
and two hundred thousand people dying in a hurricane.
Granted, acquiring evidence is often hard because of so many conflicting reports, which is why it's so
important to get experts to explain what they know
and what they don't know
clearly and precisely.
The bottom line: For the three major climate impacts of fossil fuels—the greenhouse, fertilizer, and en-
ergy effects—we want to know how they work and how they affect us, all the while asking, “How do we
know?”
CLIMATE LIVABILITY 101
To understand how each climate-related effect of fossil fuels works, we need to be clear on what exactly
we're talking about when we talk about climate and climate livability. And a good place to begin is with
the atmosphere.
The atmosphere is the mixture of gases around the Earth (held by its gravitational field) that makes life
possible with oxygen (that humans breathe), carbon dioxide (that plants breathe), nitrogen (that plants eat),
et cetera. It is a fascinating, fluid system that causes the heat of the sun and the water of the oceans and the
plant life on the Earth's surface to lead to all kinds of local weather conditions around the globe.
Weather
refers to present, near-term atmospheric conditions, especially temperatures and precipitation.
At any given time on Earth, there exists a huge range of colder and warmer climates with different weather
patterns that have different benefits and risks for human life.
Climate
is the longer-term (usually measured
in thirty-year increments) weather trends in a given region: how hot and cold it gets, how much precipit-
ation there is, what kind of storms pop up, et cetera. The global climate system is the sum of atmospheric
conditions around the globe over time.
Talk about “the climate” tends to misrepresent how climate works. It makes climate seem like
something uniform and unchanging rather than one part of a diverse, ever-changing system.
Climate change is a change in the general weather patterns on a local level. Global climate change,
often equated with climate change per se or man-made climate change, is change in the overall climate
system and its diverse subclimates. There are many factors that affect local and global climate, including
changes in the sun's intensity, and changes in plant life that alter the concentration of different elements
