The camel is called the ship of the desert. This is not only because it is strong. It is also because its body adapts to the harsh climate. Its hump stores fat, not water as many people think. The body uses this fat as a source of energy when food is scarce. Its long eyelashes protect its eyes from sand, and it can close its nostrils during storms. Its wide foot also stops it from sinking into the sand. A camel can go for days without a drink. But when it reaches water, it drinks a large amount in a few minutes and replaces what it lost. For this reason, the people of the Arabian Peninsula depended on it for many centuries to travel and to trade.

Question: In the phrase "harsh climate", the word "harsh" is closest in meaning to: