ABSTRACT: Towards a comprehensive Holocene temperature and precipitation record for British Columbia using a pollen-based multi-method approach.

CGRG Bibliography of Canadian Geomorphology
Search Results

Author :

Date :

Title :

Publication :

Issue :

Page(s) :

Abstract

We generate monthly temperature and precipitation parameters at 500 year intervals using pollen frequencies obtained from both published and unpublished sediment cores that span the Holocene across British Columbia (BC) and adjacent states and provinces. Our reconstructions use five pollen- based climate reconstruction models that can be augmented using other proxies in the future. We present province-wide and sub-regional trends during the Holocene and discuss limitations, applications and future directions for the climate records. Results indicate support for the role of increased summer insolation in warm early-Holocene temperatures. Winter temperatures are low in the early-Holocene but increase to a maxima at 6 cal. kyr, while summer temperatures remain stable or gradually increase from ~8 cal. kyr to the present day, although regional variations exist. Summer precipitation gradually increases during the Holocene, reaching modern levels by 6 cal. kyr, coincident with a peak in winter precipitation. Winter precipitation declines from the 6 cal. kyr peak to modern levels at ~5 cal. kyr. As with temperatures, we find regional variations in the precipitation record, as would be expected in a physiographically diverse region such as BC. These results show clear patterns of regional and temporal change for both temperature and precipitation. The analytic framework allows these reconstructions to be improved using multiple proxy records such as isotope and chironomid-based climate reconstructions. It is our hope that this research can be used to inform future studies on climatically driven biological, geological and anthropogenic changes.

Bibliography of Canadian Geomorphology