.ASPEUTS OF STRESS IN THE TROPICAL MARINE ENVIRONMENT
219
O N
60 -
4020.
a l
U
.z 0 -
-
0
-I
20 -
4 0 .
6 0 -
temperatures. This introduces an error, but probably not a serious one
since we are concerned only with displaying an array of localities in
their correct order of temperature. A considerable part of our biological
data is taken from shallow water stations along the American coasts
and fortunately the Coast and Geodetic Survey of the United States
(1962,1965) provides temperatures for these waters. These publications
also include salinities.
The trend in mean temperature in relation to latitude hardly needs
discussion. The distribution of seasonal temperature range, though, is
*O 1
OS 00 I 0 2 4 6 8 1 0 12
Seasonal temperature range - ' C
FIU. 1. Relation of seasonal temperature range to latitude in oceanio surfaoe waters.
frequently misunderstood. It has been stated that there is no seasonal
change of temperature in tropical waters, and this statement is misleading. If we take the seasonal range in sea surface temperatures for
all oceans, we have extensive data which present a clear picture of
latitudinal distribution, but are not truly representative of inshore
conditions (Fig. 1). Data from the Coast and Geodetic Survey stations
on the east and west coasts of America are less extensive, but are truly
coastal values. We may, for purposes of comparison, consider latitudes
between 20"N and 20"s as tropical, and from 30" to 60" in both hemispheres as temperate. The ratio of mean temperate to mean tropical
seasonal ranges is then 2-5 : 1 for ocean surface values and 4.2 : 1 for
219
O N
60 -
4020.
a l
U
.z 0 -
-
0
-I
20 -
4 0 .
6 0 -
temperatures. This introduces an error, but probably not a serious one
since we are concerned only with displaying an array of localities in
their correct order of temperature. A considerable part of our biological
data is taken from shallow water stations along the American coasts
and fortunately the Coast and Geodetic Survey of the United States
(1962,1965) provides temperatures for these waters. These publications
also include salinities.
The trend in mean temperature in relation to latitude hardly needs
discussion. The distribution of seasonal temperature range, though, is
*O 1
OS 00 I 0 2 4 6 8 1 0 12
Seasonal temperature range - ' C
FIU. 1. Relation of seasonal temperature range to latitude in oceanio surfaoe waters.
frequently misunderstood. It has been stated that there is no seasonal
change of temperature in tropical waters, and this statement is misleading. If we take the seasonal range in sea surface temperatures for
all oceans, we have extensive data which present a clear picture of
latitudinal distribution, but are not truly representative of inshore
conditions (Fig. 1). Data from the Coast and Geodetic Survey stations
on the east and west coasts of America are less extensive, but are truly
coastal values. We may, for purposes of comparison, consider latitudes
between 20"N and 20"s as tropical, and from 30" to 60" in both hemispheres as temperate. The ratio of mean temperate to mean tropical
seasonal ranges is then 2-5 : 1 for ocean surface values and 4.2 : 1 for