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- Creator:
- Andersen, Mads S., Andersen, Simone T., Nielsen, Ole John, Solling, Theis I., Osterstrom, Freja F., and Andersen, Mads P.
- Description:
- The atmospheric fates of Z- and E-CF3CH[double bond, length as m-dash]CHCF3 have been studied, investigating the kinetics and the products of the reactions of the two compounds with Cl atoms, OH radicals, OD radicals, and O3. FTIR smog chamber experiments measured: k(Cl + Z-CF3CH[double bond, length as m-dash]CHCF3) = (2.59 ± 0.47) × 10−11, k(Cl + E-CF3CH[double bond, length as m-dash]CHCF3) = (1.36 ± 0.27) × 10−11, k(OH + Z-CF3CH[double bond, length as m-dash]CHCF3) = (4.21 ± 0.62) × 10−13, k(OH + E-CF3CH[double bond, length as m-dash]CHCF3) = (1.72 ± 0.42) × 10−13, k(OD + Z-CF3CH[double bond, length as m-dash]CHCF3) = (6.94 ± 1.25) × 10−13, k(OD + E-CF3CH[double bond, length as m-dash]CHCF3) = (5.61 ± 0.98) × 10−13, k(O3 + Z-CF3CH[double bond, length as m-dash]CHCF3) = (6.25 ± 0.70) × 10−22, and k(O3 + E-CF3CH[double bond, length as m-dash]CHCF3) = (4.14 ± 0.42) × 10−22 cm3 molecule−1 s−1 in 700 Torr of air/N2/O2 diluents at 296 ± 2 K. E-CF3CH[double bond, length as m-dash]CHCF3 reacts with Cl atoms to give CF3CHClC(O)CF3 in a yield indistinguishable from 100%. Z-CF3CH[double bond, length as m-dash]CHCF3 reacts with Cl atoms to give (95 ± 10)% CF3CHClC(O)CF3 and (7 ± 1)% E-CF3CH[double bond, length as m-dash]CHCF3. CF3CHClC(O)CF3 reacts with Cl atoms to give the secondary product CF3C(O)Cl in a yield indistinguishable from 100%, with the observed co-products C(O)F2 and CF3O3CF3. The main atmospheric fate for Z- and E-CF3CH[double bond, length as m-dash]CHCF3 is reaction with OH radicals. The atmospheric lifetimes of Z- and E-CF3CH[double bond, length as m-dash]CHCF3 are estimated as 27 and 67 days, respectively. IR absorption cross sections are reported and the global warming potentials (GWPs) of Z- and E-CF3CH[double bond, length as m-dash]CHCF3 for the 100 year time horizon are calculated to be GWP100 = 2 and 7, respectively. This study provides a comprehensive description of the atmospheric fate and impact of Z- and E-CF3CH[double bond, length as m-dash]CHCF3.
- Resource Type:
- Article
- Identifier:
- 1463-9076
- Campus Tesim:
- Northridge
- Creator:
- Melendez, Melissa, Carlton, Renee, Bates, Nicholas, Watanabe, Atsushi, Dunbar, Rob, Manzello, Derek, Schulz, Kai, Koweek, David, Kayanne, Hajime, Kline, David I., Lazar, Boaz, Andersson, Andreas, Enochs, Ian, Caldeira, Ken, Corredor, Jorge, Langdon, Chris, Suzuki, Atsushi, Lantz, Coulson A., Silverman, Jacob, Teneva, Lida, Gattuso, Jean-Pierre, Cyronak, Tyler, Yamamoto, Shoji, Santos, Isaac, Erez, Jonathan, Eyre, Bradley, Mcmahon, Ashly, Gledhill, Dwight, Shaw, Emily, Albright, Rebecca, and Page, Heather
- Description:
- Worldwide, coral reef ecosystems are experiencing increasing pressure from a variety of anthropogenic perturbations including ocean warming and acidification, increased sedimentation, eutrophication, and overfishing, which could shift reefs to a condition of net calcium carbonate (CaCO3) dissolution and erosion. Herein, we determine the net calcification potential and the relative balance of net organic carbon metabolism (net community production; NCP) and net inorganic carbon metabolism (net community calcification; NCC) within 23 coral reef locations across the globe. In light of these results, we consider the suitability of using these two metrics developed from total alkalinity (TA) and dissolved inorganic carbon (DIC) measurements collected on different spatiotemporal scales to monitor coral reef biogeochemistry under anthropogenic change. All reefs in this study were net calcifying for the majority of observations as inferred from alkalinity depletion relative to offshore, although occasional observations of net dissolution occurred at most locations. However, reefs with lower net calcification potential (i.e., lower TA depletion) could shift towards net dissolution sooner than reefs with a higher potential. The percent influence of organic carbon fluxes on total changes in dissolved inorganic carbon (DIC) (i.e., NCP compared to the sum of NCP and NCC) ranged from 32% to 88% and reflected inherent biogeochemical differences between reefs. Reefs with the largest relative percentage of NCP experienced the largest variability in seawater pH for a given change in DIC, which is directly related to the reefs ability to elevate or suppress local pH relative to the open ocean. This work highlights the value of measuring coral reef carbonate chemistry when evaluating their susceptibility to ongoing global environmental change and offers a baseline from which to guide future conservation efforts aimed at preserving these valuable ecosystems.
- Resource Type:
- Article
- Identifier:
- 1932-6203
- Campus Tesim:
- Northridge
- Creator:
- Andersen, Mads S., Andersen, Simone T., Nielsen, Ole John, Solling, Theis I., and Osterstrom, Freja F.
- Description:
- The atmospheric fates of Z- and E-CF3CH[double bond, length as m-dash]CHCF3 have been studied, investigating the kinetics and the products of the reactions of the two compounds with Cl atoms, OH radicals, OD radicals, and O3. FTIR smog chamber experiments measured: k(Cl + Z-CF3CH[double bond, length as m-dash]CHCF3) = (2.59 ± 0.47) × 10−11, k(Cl + E-CF3CH[double bond, length as m-dash]CHCF3) = (1.36 ± 0.27) × 10−11, k(OH + Z-CF3CH[double bond, length as m-dash]CHCF3) = (4.21 ± 0.62) × 10−13, k(OH + E-CF3CH[double bond, length as m-dash]CHCF3) = (1.72 ± 0.42) × 10−13, k(OD + Z-CF3CH[double bond, length as m-dash]CHCF3) = (6.94 ± 1.25) × 10−13, k(OD + E-CF3CH[double bond, length as m-dash]CHCF3) = (5.61 ± 0.98) × 10−13, k(O3 + Z-CF3CH[double bond, length as m-dash]CHCF3) = (6.25 ± 0.70) × 10−22, and k(O3 + E-CF3CH[double bond, length as m-dash]CHCF3) = (4.14 ± 0.42) × 10−22 cm3 molecule−1 s−1 in 700 Torr of air/N2/O2 diluents at 296 ± 2 K. E-CF3CH[double bond, length as m-dash]CHCF3 reacts with Cl atoms to give CF3CHClC(O)CF3 in a yield indistinguishable from 100%. Z-CF3CH[double bond, length as m-dash]CHCF3 reacts with Cl atoms to give (95 ± 10)% CF3CHClC(O)CF3 and (7 ± 1)% E-CF3CH[double bond, length as m-dash]CHCF3. CF3CHClC(O)CF3 reacts with Cl atoms to give the secondary product CF3C(O)Cl in a yield indistinguishable from 100%, with the observed co-products C(O)F2 and CF3O3CF3. The main atmospheric fate for Z- and E-CF3CH[double bond, length as m-dash]CHCF3 is reaction with OH radicals. The atmospheric lifetimes of Z- and E-CF3CH[double bond, length as m-dash]CHCF3 are estimated as 27 and 67 days, respectively. IR absorption cross sections are reported and the global warming potentials (GWPs) of Z- and E-CF3CH[double bond, length as m-dash]CHCF3 for the 100 year time horizon are calculated to be GWP100 = 2 and 7, respectively. This study provides a comprehensive description of the atmospheric fate and impact of Z- and E-CF3CH[double bond, length as m-dash]CHCF3.
- Resource Type:
- Article
- Identifier:
- 1463-9076
- Campus Tesim:
- Northridge
- Creator:
- Kandaris, Alexa and Barton, Samantha
- Description:
- In 2006 the California State Assembly passed Assembly Bill 32, or the California Global Warming Solutions Act. AB-32 appointed the Air Resources Board as lead agency to implement a reduction in greenhouse gas (GHG) emissions back to 1990 levels by 2020. One of the ways that the ARB is facilitating this reduction is through the development and implementation of California's first GHG emissions cap and trade program. The program sets a maximum amount of allowable emissions for the industry (the "cap") then enables individual businesses to "trade" emissions allowances . Trading creates incentives to reduce GHGs below allowable levels through investments in clean technologies.
- Resource Type:
- Poster
- Campus Tesim:
- Humboldt
- Department:
- Economics