continental interior to the east coast, lies the
humid, warm-summer, continental climate.
Located squarely between the source regions of
polar continental air masses to the north, and
maritime or continental tropical air masses to
the south, it is subject to strong seasonal contrasts
in temperature as air masses push back and forth
across the continent.
This climate occurs only in the Northern
Hemisphere. It applies to the northeastern United
States and southeastern Canada, southeastern
Siberia, and northern Japan. Very similar climatic conditions also hold for eastern Europe
across the Baltic countries and Russia as far as
the Urals.
The Ko ¨ppen-Trewartha system designates this
area as Dcb, a cold, snowy, winter climate with a
warm summer (see Fig. 6.3, climate diagram for
Moskva, Russia). This climate has 4–7 months
when temperatures exceed 10
C, with no dry
season. The average temperature during the
coldest month is below 0
C. The warm summer
signified by the letter b has an average temperature during its warmest month that never exceeds
22
C. Precipitation is ample all year, but substantially greater during the summer. In eastern
Asia, a monsoon effect is strongly accentuated in
summer.
Mixed boreal and deciduous forest grows
throughout the colder northern parts of the
humid continental climate zone (Fig. 6.4), and
is therefore transitional between the boreal forest
to the north and the deciduous forest to the south.
In eastern North America, part of it consists of
mixed stands of a few coniferous species (mainly
pine) and few deciduous species (mainly birch,
maple, and beech). The rest is a macromosaic of
pure deciduous forest in favorable habitats, with
good soil and pure coniferous forest in less favorable habitats with poor soils. Here soils are
Fig. 6.2 Divisions of the continental humid temperate domain
6.2 210 Warm Continental Division
57
humid, warm-summer, continental climate.
Located squarely between the source regions of
polar continental air masses to the north, and
maritime or continental tropical air masses to
the south, it is subject to strong seasonal contrasts
in temperature as air masses push back and forth
across the continent.
This climate occurs only in the Northern
Hemisphere. It applies to the northeastern United
States and southeastern Canada, southeastern
Siberia, and northern Japan. Very similar climatic conditions also hold for eastern Europe
across the Baltic countries and Russia as far as
the Urals.
The Ko ¨ppen-Trewartha system designates this
area as Dcb, a cold, snowy, winter climate with a
warm summer (see Fig. 6.3, climate diagram for
Moskva, Russia). This climate has 4–7 months
when temperatures exceed 10
C, with no dry
season. The average temperature during the
coldest month is below 0
C. The warm summer
signified by the letter b has an average temperature during its warmest month that never exceeds
22
C. Precipitation is ample all year, but substantially greater during the summer. In eastern
Asia, a monsoon effect is strongly accentuated in
summer.
Mixed boreal and deciduous forest grows
throughout the colder northern parts of the
humid continental climate zone (Fig. 6.4), and
is therefore transitional between the boreal forest
to the north and the deciduous forest to the south.
In eastern North America, part of it consists of
mixed stands of a few coniferous species (mainly
pine) and few deciduous species (mainly birch,
maple, and beech). The rest is a macromosaic of
pure deciduous forest in favorable habitats, with
good soil and pure coniferous forest in less favorable habitats with poor soils. Here soils are
Fig. 6.2 Divisions of the continental humid temperate domain
6.2 210 Warm Continental Division
57