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Task 1. Read the following text, translate it into Ukrainian (in written form).

Geologic Processes in Arid Climates
Weathering. In humid regions, relatively well-developed soils support an almost
continuous cover of vegetation. Here the slopes and rock edges are rounded, reflecting the strong
influence of chemical weathering in a humid climate. By contrast, much of the weathered debris
in deserts consists of unaltered rock and mineral fragments—the results of mechanical
weathering processes. In dry lands, rock weathering of any type is greatly reduced because of the
lack of moisture and the scarcity of organic acids from decaying plants. However, chemical
weathering is not completely lacking in deserts. Over long periods of time, clays and thin soils
do form, and many iron-bearing silicate minerals oxidize, producing the rust-colored stain found
tinting some desert landscapes.
The Role of Water. Permanent streams are normal in humid regions, but almost all
desert stream beds are dry most of the time. Deserts have ephemeral streams which means that
they carry water only in response to specific episodes of rainfall. A typical ephemeral stream
might flow only a few days or perhaps just a few hours during the year. In some years, the
channel might carry no water at all. This fact is obvious even to the casual traveller who notices
numerous bridges with no streams beneath them or numerous dips in the road where dry
channels cross. However, when the rare heavy showers do come, so much rain falls in such a
short time that all of it cannot soak.
Because desert vegetative cover is sparse, runoff is largely unhindered and consequently
rapid, often creating flash floods along valley floors. These floods are quite unlike floods in
humid regions. A flood on a river such as the Mississippi may take several days to reach its crest
and then subside, but desert floods arrive suddenly and subside quickly. Because much of the
surface material in a desert is not anchored by vegetation, the amount of erosional work that
occurs during a single, short-lived rain event is impressive.
In the dry western United States, different names are used for ephemeral streams,
including wash and arroyo. In other parts of the world, a dry stream may be a wadi (Arabia and
North Africa), a donga (South Africa), or a nullah (India).
Humid regions are notable for their integrated drainage systems, but in arid regions
streams usually lack an extensive system of tributaries. In fact, a basic characteristic of desert
streams is that they are small and die out before reaching the sea. Because the water table is
usually far below the surface, few desert streams can draw upon it as streams do in humid
regions. Without a steady supply of water, the combination of evaporation and infiltration soon
depletes the stream.
It should be emphasized that running water, although infrequent, nevertheless does most
of the erosional work in deserts. This is contrary to a common belief that wind is the most
important erosional agent sculpting desert landscapes. Although wind erosion is indeed more
significant in dry areas than elsewhere, most desert landforms are carved by running water. The
main role of wind is in the transportation and deposition of sediment, which creates and shapes
the ridges and mounds we call dunes.

Task 2. Build up a glossary to the most important terms used in the text.

Task 3. Answer the questions:
1. How does the process of weathering influence arid climates?
2. What is the main role of water in arid climates?
3. What is the most important erosional agent in deserts?

Task 4. Retell the text using the glossary from Task 2.