Holocene winter climate variability in Central and Eastern Europe.

Area of Science:

• Paleoclimatology
• European climate history
• Stable isotope analysis

Background:

• Limited Holocene winter climate reconstructions exist for Europe.
• Existing data often lack sufficient length or resolution.
• Understanding past winter conditions is crucial for climate modeling.

Purpose of the Study:

• To present a detailed Holocene winter climate record for East-Central Europe.
• To reconstruct air temperature and moisture source changes over the past 10,000 years.
• To analyze shifts in atmospheric circulation patterns and their drivers.

Main Methods:

• Stable isotopic analysis of an ice core from the Romanian Carpathian Mountains.
• Reconstruction of late autumn through early winter air temperature.
• Analysis of moisture source variations and atmospheric circulation.

Main Results:

• Holocene temperatures generally followed insolation trends, peaking in the mid-to-late Holocene.
• Atmospheric circulation shifted from a negative North Atlantic Oscillation (NAO) phase in the early Holocene to a positive NAO phase in the late Holocene.
• The 8.2 kcal BP cooling event was marked by a moisture source shift, indicating weaker westerlies and increased Mediterranean cyclone activity.

Conclusions:

• The Romanian Carpathian ice core provides a valuable long-term winter climate proxy for Europe.
• Abrupt shifts in atmospheric circulation, such as the NAO phase transition, significantly impacted regional climate.
• Past climate events, like the 8.2 kcal BP cooling, manifested differently in temperature and moisture sources, offering insights into complex climate dynamics.