Increases in temperature and precipitation can affect Reindeer pastures in a variety of ways that may influence conditions for reindeer. For instance, increased temperature in autumn can delay both the arrival of snow, as a result of which the reindeer tend to disperse and the herds become less easy to control, and also the formation of thick, safe ice over rivers and lakes, consequently impeding the movement of herds inland. Increased precipitation in winter can result in greater accumulation of snow on winter pastures resulting in a general reduction in the availability of forage.