V. NEW APPROACH TO WATER RELATIONS OF DESERT PLANTS
227
Fig. 8. Representative climate diagrams for the different types of arid regions
(continued). (J) Denkoi (Inner Mongolia), (K) Alice Springs (Central Australia),
(L) Arequipa (Peru), (M) Arica (Northern Chile), (N) Swakopmund (Southwest
Africa), (O) Adrar (Algeria), (P) Assuan (Egypt). The climate diagrams (Figs.
7 and 8) are graphical representations for the climate for a given location. The
x axis is divided into 12 equal sections corresponding to the month of the year
and beginning with January for stations on the Northern Hemisphere and with
July for locations on the Southern Hemisphere. On the y axis the monthly means
of temperature (in °C, thin line) and of precipitation (in mm, thick line) are
plotted, beginning with 0°C and 0 mm precipitation at y = 0. One division corresponds to 10°C and 20 mm. In this presentation a dry season is indicated when
the temperature curve is above the curve for precipitation, while a humid period
exists during times when the temperature curve is below the curve for precipitation.
The respective areas are dotted or hatched. The name of the location and its
elevation are indicated inside the upper left corner of the climate diagram. The
figures in brackets below this name indicate the number of years of observations
(when two numbers, the first indicates the length for the temperature record and
the second one the number of years for the records of the precipitation). The
first number in the right upper corner indicates annual mean temperature in °C
and the second, the annual precipitation in mm. The upper number outside the
diagram in the upper left-hand corner gives absolute maximum temperature for
the hottest month and the lower number the average daily maximum for the hottest
month. The number at the lower left corner indicates the mean of the daily minima
of the coldest month and the figure below it gives the lowest recorded temperature.
Locations in tropic regions have a monthly mean temperature which fluctuates
very little, although the daily variations may be considerable. To indicate their
amplitude the mean daily temperature variation of the warmest month is given
at the left side of the diagram at the level of the temperature line (e.g., for
diagram B, Fig. 7, the mean daily temperature variation is 9.8°C). The hatched
blocks below the x axis indicate months with frost, where an absolute minimum
below 0°C was observed at least on one day. (From Walter and Lieth, 1967.)
227
Fig. 8. Representative climate diagrams for the different types of arid regions
(continued). (J) Denkoi (Inner Mongolia), (K) Alice Springs (Central Australia),
(L) Arequipa (Peru), (M) Arica (Northern Chile), (N) Swakopmund (Southwest
Africa), (O) Adrar (Algeria), (P) Assuan (Egypt). The climate diagrams (Figs.
7 and 8) are graphical representations for the climate for a given location. The
x axis is divided into 12 equal sections corresponding to the month of the year
and beginning with January for stations on the Northern Hemisphere and with
July for locations on the Southern Hemisphere. On the y axis the monthly means
of temperature (in °C, thin line) and of precipitation (in mm, thick line) are
plotted, beginning with 0°C and 0 mm precipitation at y = 0. One division corresponds to 10°C and 20 mm. In this presentation a dry season is indicated when
the temperature curve is above the curve for precipitation, while a humid period
exists during times when the temperature curve is below the curve for precipitation.
The respective areas are dotted or hatched. The name of the location and its
elevation are indicated inside the upper left corner of the climate diagram. The
figures in brackets below this name indicate the number of years of observations
(when two numbers, the first indicates the length for the temperature record and
the second one the number of years for the records of the precipitation). The
first number in the right upper corner indicates annual mean temperature in °C
and the second, the annual precipitation in mm. The upper number outside the
diagram in the upper left-hand corner gives absolute maximum temperature for
the hottest month and the lower number the average daily maximum for the hottest
month. The number at the lower left corner indicates the mean of the daily minima
of the coldest month and the figure below it gives the lowest recorded temperature.
Locations in tropic regions have a monthly mean temperature which fluctuates
very little, although the daily variations may be considerable. To indicate their
amplitude the mean daily temperature variation of the warmest month is given
at the left side of the diagram at the level of the temperature line (e.g., for
diagram B, Fig. 7, the mean daily temperature variation is 9.8°C). The hatched
blocks below the x axis indicate months with frost, where an absolute minimum
below 0°C was observed at least on one day. (From Walter and Lieth, 1967.)