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Radiative Cooling Forms Siberian High; Peaks in January–February, Drives Northeast Monsoon
The Siberian High draws attention due to strong winter activity influencing cold weather across parts of Asia, including India. It forms through radiative cooling, peaks in January–February, and drives the northeast monsoon in East and South Asia.
Siberian High (Asiatic High / Siberian Anticyclone) :
| Dimension | Key Details |
|---|---|
| Type | Intense system of cold, dry air and high atmospheric pressure that controls winter weather across Eurasia. |
| Location | Centered near Lake Baikal in Siberia. |
| Other names | Also known as the Asiatic High and the Siberian anticyclone. |
| Intensity (pressure) | Exceeding 1040 millibars; described as the strongest semi-permanent high-pressure system in the Northern Hemisphere. |
| Vertical extent | Shallow system, rarely persisting above altitudes of 3,000 meters (10,000 feet). |
| Nature of air | Extremely cold and dry air. |
| Formation mechanism | Governed by radiative cooling over the vast Asian landmass during long winter nights; heat escapes into space, causing near-surface air to become dense, heavy, and cold. |
| Seasonal peak | Reaches maximum strength in midwinter (January/February). |
| Monsoon linkage | Northeast monsoon in East and South Asia. |
| Summer condition | The system is replaced by the Asiatic Low, which brings the summer monsoon. |
| Climatic drivers of variability | Arctic Oscillation (AO)/North Atlantic Oscillation (NAO), ENSO (El Niño–Southern Oscillation), Eurasian snow cover, and climate change (Arctic amplification). |
| AO/NAO phase linkage | Negative AO provides for a stronger Siberian High; Positive AO provides for a weaker high. |
| ENSO linkage | El Niño years may weaken the Siberian High; La Niña can strengthen it (not always consistent). |
| Eurasian snow cover | Greater autumn snow cover provides for a stronger winter Siberian High. |
| Climate change | Arctic amplification may reduce temperature gradients, potentially weakening the Siberian High; episodic extreme cold events may persist. |
| Impact on India | Drives cold northerly winds towards India; provides for cool winters in North India. |
| Himalayan barrier | The Himalayas generally block the most extreme cold associated with the Siberian High. |
| La Niña condition and southward movement | During La Niña conditions, the Siberian High can overcome the Himalayan barrier and move southward. |