Why is the annual range of temperature high in the Siberian plains?
The annual range of temperature is high in the Siberian plains due to continentality. The Siberian plains are located in the interior of the Eurasian continent, far away from the moderating influence of the oceans.
As a result, the region experiences extreme temperatures with the highest range exceeding 60°C between January and July. In January, the mean temperature in the Eurasian continental interior drops to -18°C to -48°C, while summers are relatively warmer. Since land heats up and cools down much faster than water, areas deep inside large continents like Siberia show a very high annual range of temperature.
Explanation
The textbook explicitly states that the highest range of temperature (more than 60°C) is found over the north-eastern part of the Eurasian continent 'due to continentality.' The context also mentions that the mean January temperature in the Eurasian continental interior ranges from -18°C to -48°C, showing extreme cold. The northern hemisphere has larger land surface area, making the effects of land mass well pronounced. This question tests the student's understanding of how continentality affects temperature variation in interior continental regions.