Introduction:

Tree rings play a significant role for the reconstruction of climate variables on century scales.

Objective:

To reconstruct the variability of precipitation for the western part of the state of Chihuahua, based on tree rings of Pseudotsuga menziesii (Mirb.) Franco, Pinus arizonica Engelm. and Pinus strobiformis Engelm.

Materials and methods:

Samples were extracted with a Pressler drill, dated and growth indexes were generated based on dendrochronological techniques. A correlation analysis was run between regional chronology and observed precipitation data. A regression model was used to reconstruct precipitation. A spectral analysis determined the recurrence of droughts and the influence of El Niño Southern Oscillation (ENSO) on precipitation variability.

Results and discussion:

The relationship between the chronologies was statistically significant and a regional series of 359 years was developed. October-June precipitation had the highest impact on growth (r = 0.73, P < 0.01), so the variability of precipitation for that period was reconstructed for the last 359 years. Severe droughts were detected in the periods 1751-1768, 1807-1810 and 1945-1956 and a recurrence of droughts every 50 years was identified. The reconstructed precipitation variability is significantly modulated by ENSO at different time scales and frequencies.

Conclusion:

Paleoclimatic series help us to spread the knowledge of climate in specific geographic regions and to analyze the recurrence of extreme events (droughts).

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