A review of Holocene climate and oceanography of the Western United States and Northeast Pacific
Abstract
In order to understand and contextualize modern climate change, we must improve our understanding of climatic and oceanographic changes in the Holocene (11.65 kya-present). Climate records of the Holocene can be utilized as a "baseline" from which to compare modern climate and can also provide insights into how environments and ecosystems (that are climatically and tectonically similar to present) experience and recover from environmental change. However, individual studies on Holocene climate in the literature tend to focus on (1) a distinct geographic location (2) a specific proxy record or (3) a certain aspect of climate (i.e. upwelling or precipitation), resulting in localized, record-specific trends rather than a comprehensive view of climate variability through the Holocene. Here we aim to synthesize the major oceanographic and atmospheric changes that have occurred in the coastal Western United States (bounded by 30°N to 47°N and 115°W to 130°W) through the most recent 11.65 ky and explore the impacts of these major changes on marine and terrestrial ecosystems and human populations. We combine interpretations from multiple records including dendrochronology, marine sediments, lacustrine sediments, speleothems, and archeological records. Our analysis shows linkages between terrestrial and oceanographic conditions, distinct environmental phases through time, and differences in the timing of change between Northern and Southern Western U.S.. Generally, the climate is warmer from the start of the Holocene through 5.5-3 kya and then switches to a cooler climate; importantly though, the timing of this transition varies geographically. The most recent 2 kya generally shows the most variable climate. Further, we investigate both the impacts of climate change on human populations and human impact on Holocene climate. We present the results of our analyses as a temporal analysis of Western U.S. climate throughout the Holocene.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFMGC11G1122P
- Keywords:
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- 3305 Climate change and variability;
- ATMOSPHERIC PROCESSES;
- 3344 Paleoclimatology;
- ATMOSPHERIC PROCESSES;
- 1616 Climate variability;
- GLOBAL CHANGE;
- 1620 Climate dynamics;
- GLOBAL CHANGE