Carlos Sierra

View Calendar
March 1, 2021 11:30 am - 12:30 pm

Transit time of carbon and the climate benefit of sequestration in terrestrial ecosystems

Ecosystems play a fundamental role in climate change mitigation by photosynthetically fixing carbon from the atmosphere and storing it for a period of time in organic matter. Although climate impacts of carbon emissions by sources can be quantified by global warming potentials, the appropriate formal metrics to assess climate benefits of carbon removals by sinks are unclear. We introduce here the climate benefit of sequestration (CBS), a metric that quantifies the radiative effect of fixing carbon dioxide from the atmosphere and retaining it for a period of time in an ecosystem before releasing it back as the result of respiratory processes and disturbances. In order to quantify CBS, we present a formal definition of carbon sequestration (CS) as the integral of an amount of carbon removed from the atmosphere stored over the time horizon it remains within an ecosystem. Both metrics incorporate the separate effects of (i) inputs (amount of atmospheric carbon removal) and (ii) transit time (time of carbon retention) on carbon sinks, which can vary largely for different ecosystems or forms of management. These metrics can be useful for comparing the climate impacts of carbon removals by different sinks over specific time horizons, to assess the climate impacts of ecosystem management, and to obtain direct quantifications of climate impacts as the net effect of carbon emissions by sources versus removals by sinks.

Related upcoming events

  • October 3, 2022 11:30 am - October 3, 2022 12:30 pm

    Methane Plume Mapping Over Offshore Oil and Natural Gas Platforms in the Gulf of Mexico

    Alana Ayasse

    Research Scientist

    Carbon Mapper

    University of Arizona

    Abstract

    Offshore oil and natural gas platforms are responsible for about 30% of global oil and natural gas production. Despite the large share of global production there is little known about the greenhouse gas emissions from these production facilities. Given the lack of direct measurements, studies that seek to understand the greenhouse gas contribution of offshore oil and gas platforms are incredibly important. The use of airborne remote sensing to map greenhouse gases from onshore oil and gas infrastructure has become a prominent method to quantify and attribute large individual emissions to their sources. However, until now, this method has not been used offshore due to the lack of consistent reflected radiance over water bodies.  In this talk I will present the results from a 2021 study where we used visible/infrared imaging spectrometer data collected over the Gulf of Mexico to map methane emissions from shallow water offshore oil and natural gas platforms. I will discuss the methods we employed to map methane in the offshore environment and how that differs from the onshore environment. I will show how remote sensing can efficiently observe offshore infrastructure, quantify methane emissions, and attribute those emissions to specific infrastructure types.

    Bio

    Dr Alana Ayasse is a research scientist at Carbon Mapper and the University of Arizona. She earned her BA in Geography and Environmental Studies from UCLA and her PhD in Geography from UCSB. Her research focuses on improving remote sensing techniques to map methane and carbon dioxide plumes, understanding the role of satellites in a global carbon monitoring system, and using remote sensing data to further understand trends in carbon emissions.

  • October 10, 2022 11:30 am - October 10, 2022 12:30 pm

    TBD

  • October 17, 2022 11:30 am - October 17, 2022 12:30 pm

    TBD

  • October 24, 2022 11:30 am - October 24, 2022 12:30 pm

    TBD

  • October 31, 2022 11:30 am - October 31, 2022 12:30 pm

    TBD

  • November 7, 2022 11:30 am - November 7, 2022 12:30 pm

    TBD

  • November 14, 2022 11:30 am - November 14, 2022 12:30 pm

    TBD

  • November 21, 2022 11:30 am - November 21, 2022 12:30 pm

    TBD

  • November 28, 2022 11:30 am - November 28, 2022 12:30 pm

    TBD

  • December 5, 2022 11:30 am - December 5, 2022 12:30 pm

    TBD