Coastal California captures a wide array of microclimates and unique vegetation zones, many of which are vulnerable to modern climate change. There is no clear consensus about how hydroclimate, or the seasonality, amount, and severity of rainfall, will change in response to rising temperatures. Increased rainfall variability has direct impacts on fragile ecosystems. We use long chain fatty acids from terrestrial vegetation to create hydrogen (δD) and carbon (δ13C) isotope records spanning the Last Interglacial along the California margin, on a latitudinal gradient from site 1012B (32⁰N) to Clear Lake (39⁰N). The Last Interglacial is cited as a good analogue for modern climate change, and these paired proxy records provide insight into hydroclimate and vegetation changes in response to climate change. We find considerable δDp enrichment at site 1012B and Clear Lake during the peak of the Last Interglacial (MIS5e) that is consistent with other hydroclimate records from the western US. Despite similar δDp signatures, we propose different hydroclimate change mechanisms for the isotopic shift. At site 1012B, increased sea surface temperatures on the southern California margin led to convective summer rainfall, resulting in enriched leaf wax δDp values, while Clear Lake δDp changes are more likely linked to changes in northern California upwelling strength. δ13C values indicate there was not a prominent shift in plant functional type during the time examined in either site, however, high resolution pollen records are paired with isotope data to show ecosystem changes in response to rising temperatures and shifting hydroclimate regimes. Rising sea surface temperatures on the California margin are likely to change rainfall patterns in the future. The Last Interglacial elucidates key climatic and ecological processes and yields insights on how coastal California ecosystems may be impacted by modern climate change.
Meeting Place: Baltimore Woods Nature Center
4007 Bishop Hill Rd, Marcellus, NY 13108
Please bring your own high-visibility vest and closed-top shoes (safety-toed boots are recommended). Please also bring safety glasses if you plan to use a rock hammer at the outcrop stop. It is also recommended that you protect yourself against biting insects. This field trip will proceed rain or shine.
This field trip has been submitted to NYSCPG for approval of 2.5 PDH credits for NYS P.G.s.
Limit = 14 participants.
Attendees desiring PDH credits must pay for PDH credits at the time of registration (see the check box on your registration invoice).
Course Instructor: Guy Swenson, P.G. (Ramboll)
Arrive at Baltimore Woods Nature Center at 8:00 a.m. We will leave the meeting point at 8:30 a.m. Participants will carpool from the meeting point to all stops.
Field Trip Outline:
Introduction Health & Safety Objectives Bedrock Geology of Area Glacial Geology of Area Overview of Field Trip Stops Stop at Marcellus Shale Outcrop Stop for View of Disappearing Lake Area Landslide Stop Learning Assessment Questions
Introduction
Health & Safety
Objectives
Bedrock Geology of Area
Glacial Geology of Area
Overview of Field Trip Stops
Stop at Marcellus Shale Outcrop
Stop for View of Disappearing Lake Area
Landslide Stop
Learning Assessment Questions
Arrive at Baltimore Woods Nature Center at 1:00 p.m. We will leave the meeting point at 1:30 p.m. Participants will carpool from the meeting point to all stops.