Vietnam War: Forest Fire as a Military Weapon - Paperless Archives

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PERTINENT INCENDIARY DATA BY CLIMATIC TYPE
The key to identification of each fire climate class is shown in Table 5, page 35, of the text. The representative
locations given for each class are listed, from top to bottom, in order of decreasing winter temperatures. In most cases, the
warmest location shown for a class (for example, the first location for MI-HUSB) is very similar to the coolest location
for another class (the last location for FF- HUSB). Likewise, the wettest location is a class (such as CL- HULB) often
is similar to the driest in another class (such as CL-HUSB).
Descriptions of the fire climates by world climate classes and by precipitation patterns are from Papadakis, footnote
13. page 34, of the text.
Humid months ("H"), dry months ("D"), and burn months ("B") are described on pages 34 to 37. Procedures for
determining the (+) and (-) humidity values are on pages 29 to 31.
In the graphs of climates at representative locations, the temperature and precipitation scales are adapted from the
criteria of Bagnoulsiý The period of plant moisture stress corresponds closely with the time, or times of the year when
the curve for average monthly precipitation lies below the curve for average monthly mean temperature.
The date, or dates, recommended for herbicide applications at each location illustrated in Figures BI - B27 represent
a satisfactory combination of air temperature and soil moisture, and allow maximum feasible time for dying and drying of
vegetation before burning. At other locations having the same climate, some adjustments in treatment dates may be
necessary to fit a somewhat different yearly weather pattern. The herbicide dosages should be increased if treatments are
to be applied under other than the most satisfactory weather conditions, as explained on pages 63 to 65 of the text.
CLIMATE FF-HUYL
FROSTFREE WINTER; HUMID YEARLONG
All equatorial and frostfree tropical climates having no "D" months and no "B" months. Examples are:
Precipitation No. of Months Yearly Humidity Values
Location Pattern "H" "D '"B" () O
Andagoya, Colombia Humid 12 0 0 +480 0
Kuala Lumpur, Malasia Humid I1 0 0 +454 0
Kieta, Bougainville I. Humid 12 0 0 +480 0
Guam 1. Humid 9 0 0 +351 0
San Juan, P.R. Humid I1 0 0 +431 0
Entebbe, Uganda Humid I1! 0 0 +320 0
Quang-Tri, R. V. N. Humid 7 0 0 +263 0
Santos, Brazil Humid 12 0 0 +424 0
rHamilton, Bermuda Humid 12 0 0 +416 0
Temperature: Not limiting; allows growth of tender-leaved plants.
Precipitation: Not limiting, except for short dry periods.
Bagnouls (1957) Les climates biologiques et leur classification. Ann. de Geographic, 66 (355): 193-220.
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