Units
9
ately average over heterogeneity to define properties of a representative
homogeneous substitute.
1.7 Applications
From the examples already given, it is quite obvious that environmental
biophysics can be applied to a broad spectrum of problems. Fairly complete evaluations already exist for some problems, though much work
remains to be done. Analysis of human comfort and survival in hot and
cold climates requires a good understanding of the principles we will
discuss. Preferred climates, survival, and food requirements of domestic
and wild animals can also be considered. Plant adaptations in natural systems can be understood, and optimum plant types and growing conditions
in agriculture and forestry can be selected through proper application of
these principles. Even the successful architectural design of a building,
which makes maximum use of solar heat and takes into account wind
and other climatological variables, requires an understanding of this subject. Finally, models that forecast the weather or predict changes in past
and future climates rely heavily on the principles of environmental biophysics to accommodate exchanges between the surface of the earth and
the atmosphere.
As we study environmental biophysics, we will find that people from
"primitive" cultures, and even animals, often have a far better understanding of the application of its principles than we do. Understanding
the environment and how best to interact with it often makes the difference between life and death for them, whereas for us it may just mean a
minor annoyance or an increased fuel bill.
1.8 Units
Units consistent with the Systeme International (SI) will be used in this
book. The SI base units and their accepted symbols are the meter (m) for
length, the kilogram (kg) for mass, the second (s) for time, the Kelvin
(K) for thermodynamic temperature, and the mole (mol) for the amount
of substance. Units derived from these, which we use in this book are
given in Table 1.1. Additional derived units can be found in Page and
Vigoureux (1974).
The Celsius temperature scale is more convenient for some biophysical
problems than the thermodynamic (Kelvin) scale. We will use both. By
definition C = K - 273.15. Since the Celsius degree is the same size
as the Kelvin degree, derived units with temperature in the denominator
can be written as either C-' or K-' . For example, units for specific heat
are either J kg-' C-' or J kg-' K-'. To distinguish between the two
temperature scales, we will use T in standard font for Celsius temperature,
and in bold font (T) for Kelvin temperature. Some useful factors for
converting to SI units can be found in Table A.4 in the Appendix.
9
ately average over heterogeneity to define properties of a representative
homogeneous substitute.
1.7 Applications
From the examples already given, it is quite obvious that environmental
biophysics can be applied to a broad spectrum of problems. Fairly complete evaluations already exist for some problems, though much work
remains to be done. Analysis of human comfort and survival in hot and
cold climates requires a good understanding of the principles we will
discuss. Preferred climates, survival, and food requirements of domestic
and wild animals can also be considered. Plant adaptations in natural systems can be understood, and optimum plant types and growing conditions
in agriculture and forestry can be selected through proper application of
these principles. Even the successful architectural design of a building,
which makes maximum use of solar heat and takes into account wind
and other climatological variables, requires an understanding of this subject. Finally, models that forecast the weather or predict changes in past
and future climates rely heavily on the principles of environmental biophysics to accommodate exchanges between the surface of the earth and
the atmosphere.
As we study environmental biophysics, we will find that people from
"primitive" cultures, and even animals, often have a far better understanding of the application of its principles than we do. Understanding
the environment and how best to interact with it often makes the difference between life and death for them, whereas for us it may just mean a
minor annoyance or an increased fuel bill.
1.8 Units
Units consistent with the Systeme International (SI) will be used in this
book. The SI base units and their accepted symbols are the meter (m) for
length, the kilogram (kg) for mass, the second (s) for time, the Kelvin
(K) for thermodynamic temperature, and the mole (mol) for the amount
of substance. Units derived from these, which we use in this book are
given in Table 1.1. Additional derived units can be found in Page and
Vigoureux (1974).
The Celsius temperature scale is more convenient for some biophysical
problems than the thermodynamic (Kelvin) scale. We will use both. By
definition C = K - 273.15. Since the Celsius degree is the same size
as the Kelvin degree, derived units with temperature in the denominator
can be written as either C-' or K-' . For example, units for specific heat
are either J kg-' C-' or J kg-' K-'. To distinguish between the two
temperature scales, we will use T in standard font for Celsius temperature,
and in bold font (T) for Kelvin temperature. Some useful factors for
converting to SI units can be found in Table A.4 in the Appendix.