These books are listed in order from what I consider to be the easiest to read and understand to the most complex and in depth.
Hopper, Leonard J. 2007. Landscape Architectural Graphic Standards. Ho boken, NJ: Wiley. 1074 pages.
Several sections in this book provide the basics of solar radiation, wind, climate, microclimate modification, and air quality in a form that can be used directly in design. There is a student version of the book as well, which is much smaller but retains the microclimate pieces.
Sullivan, Chip. 2002. Garden and Climate. New York: McGraw-Hill. 263 pages.
This is a beautifully illustrated book that received a national award from the American Society of Landscape Architects. The illustrations are outstanding and the text very readable, and the book provides an experiential view of microclimate modification. There are many examples of historic precedent and vernacular design.
Brown, G. Z., and Mark DeKay. 2001. Sun, Wind and Light: Architectural Design Strategies. 2nd ed. New York: Wiley. 382 pages.
This is a very well-illustrated and interesting book, but as the title suggests, it is more oriented toward architecture with relatively little about outdoor environments or human thermal comfort. However, it contains many valuable diagrams and explanations that will definitely enhance your understanding of microclimate.
Brown, Robert D., and Terry J. Gillespie. 1995. Microclimatic Landscape Design: Creating Thermal Comfort and Energy Efficiency. New York: Wiley. 193 pages.
If you want a bit more detail on any microclimatic design concepts, take a look at this book. The information is still current, but unfortunately the computer programs are out of date. Two recent papers have provided an updated version of the COMFA model: (1) N. A. Kenny, J. S. Warland, R. D. Brown, and T. J. Gillespie, Part A: Assessing the performance of the COMFA outdoor thermal comfort model on subjects performing physical activity, International Journal of Biometeorology 53(5) (2009): 415–28; and (2) N. A. Kenny, J. S. Warland, R. D. Brown, and T. J. Gillespie, Part B: Revisions to the COMFA outdoor thermal comfort model for application to subjects performing physical activity 53(5) (2009): 429–41.
Oke, T. R. 1987. Boundary Layer Climates. 2nd ed. New York: Routledge. 435 pages.
Originally published in 1978, this book has been a classic for more than three decades. In my opinion, this is the best book ever written on the science of microclimate. The theory is explained very clearly and effectively, but you have to make the connection with design yourself. If you want a more complete, in-depth understanding of microclimates, this book will provide it.
Campbell, Gaylon S., and John M. Norman. 1998. An Introduction to Environmental Biophysics. 2nd ed. New York: Springer. 286 pp.
If you read and understand Oke and want to go into even more depth, this is the book for you. It provides theoretical foundations and equations for almost all aspects of the microclimate.
There are also a couple of references on evolutionary psychology that I think are quite useful and interesting.
Ariely, D. 2008. Predictably Irrational: The Hidden Forces That Shape Our Decisions. New York: Harper Collins. 304 pages.
Baumeister, Roy F. 2005. The Cultural Animal: Human Nature, Meaning, and Social Life. New York: Oxford University Press. 450 pages.