First Principles - Sustainable Design: The Science of Sustainability and Green Engineering - page 34

and chemistry. Life systems are complicated. Cause-and-effect relationships are
complex.
The problem with increasing awareness is that it is often not well behaved. We
tell people that a model indicates that carbon dioxide increases of x megatons will
lead to warming of 1 ◦ C each decade, which could lead to melting of glaciers and
ice caps. What is not shown are the confidence intervals around the estimates,
nor the assumptions in the model that led to the result. For example, the internal
dependencies of the model are not shared or are ignored. We assume that the
presence of so much greenhouse gas will influence the greenhouse effect in Earth's
atmosphere, which in turn will increase the mean Earth temperature. We also
assume that the temperature increase will be distributed in such a way that the
melting will occur that is feared. It is quite possible that the scientists include all
of these assumptions (although I have heard some who have not) in their reports
to the media, but the reporter did not consider these “details” to be newsworthy.
So great care must be taken to ensure that what people are becoming aware of is,
in fact, what the science is saying.
This awareness step should be familiar to the design professional, who may have
difficulty keeping the client focused on the numerous, diverse details of a design.
The client may want to skip to the bottom line. What is the project cost? What
will the structure look like? When will it be built? It may only be after the client
is unhappy about any of these that the designer can explain the science behind
a design. For example, the materials needed to provide the function requested
by the client are expensive. Or, the open floor design may be incompatible with
servicing needs. Or, the schedule has some internal dependencies that cannot be
built in parallel, but must be serial.
This brings us to decision making . Given that we have done a good job of
raising awareness, the science should drive decisions. Often, this gets out in front
of awareness. We may not fully understand the problem or we may be pushed
toward a decision for reasons other than science. For example, is the dwindling
habitat of the polar bear an established fact? Or is it sufficiently sensational that we
should do something, no matter the state-of-the-science? This is a very interesting
challenge. For example, much of the world community has shifted toward the
precautionary principle for big decisions much as those revolving around global
climate change. Others, including the United States, rely mainly on a risk-based
decision approach . The difference is “onus”. The precautionary principle places the
onus on what could happen. For example, a new product is approved only if the
company claims that it can prove it to be safe. Conversely, the risk-based approach
places the onus on regulators to ask the right questions and to disapprove the
product only if based on available evidence, it presents an unacceptable risk.
The last step in decision strategy is behavior , the subject of this topic. Our belief
is that the practicing professional can better ensure green designs and sustainable
solutions in everyday practice, and we contend that success is more likely with