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The global decrease in seawater pH known as ocean acidification has important ecological consequences and is an imminent threat for numerous marine organisms. Even though the deep sea is generally considered to be a stable environment, it can be dynamic and vulnerable to anthropogenic disturbances including increasing temperature, deoxygenation, ocean acidification and pollution. Lophelia pertusa is among the better-studied cold-water corals but was only recently documented along the US West Coast, growing in acidified conditions. In the present study, coral fragments were collected at ∼300 m depth along the southern California margin and kept in recirculating tanks simulating conditions normally found in the natural environment for this species. At the collection site, waters exhibited persistently low pH and aragonite saturation states (Omega arag) with average values for pH of 7.66 +- 0.01 and Omega arag of 0.81 +- 0.07. In the laboratory, fragments were grown for three weeks in “favorable” pH/Omega arag of 7.9/1.47 (aragonite saturated) and “unfavorable” pH/ Omega arag of 7.6/0.84 (aragonite undersaturated) conditions. There was a highly significant treatment effect (P < 0.001) with an average% net calcification for favorable conditions of 0.023 +- 0.009%/d and net dissolution of −0.010 +- 0.014%/d for unfavorable conditions. We did not find any treatment effect on feeding rates, which suggests that corals did not depress feeding in low pH/ Omega arag in an attempt to conserve energy. However, these results suggest that the suboptimal conditions for L. pertusa from the California margin could potentially threaten the persistence of this cold-water coral with negative consequences for the future stability of this already fragile ecosystem. In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2019) was used to compute a complete and consistent set of carbonate system variables, as described by Nisumaa et al. (2010). In this dataset the original values were archived in addition with the recalculated parameters (see related PI). The date of carbonate chemistry calculation by seacarb is 2020-06-12.

Estimates of heritability inform evolutionary potential and the likely outcome of many management actions, but such estimates remain scarce for marine organisms. Here, we report high heritability of calcification rate among the eight most dominant Hawaiian coral species under reduced pH simulating future ocean conditions. Coral colonies were sampled from up to six locations across a natural mosaic in seawater chemistry throughout Hawaiʻi and fragmented into clonal replicates maintained under both ambient and high pCO2 conditions. Broad sense heritability of calcification rates was high among all eight species, ranging from a low of 0.32 in Porites evermanni to a high of 0.61 in Porites compressa. The overall results were inconsistent with short-term acclimatization to the local environment or adaptation to the mean or ideal conditions. Similarly, in 'local vs. foreign' and 'home vs. away' tests there was no clear signature of local adaptation. Instead, the data are most consistent with a protected polymorphism as the mechanism which maintains differential pH tolerance within the populations. Substantial individual variation, coupled with high heritability and large population sizes, imply considerable scope for natural selection and adaptive capacity, which has major implications for evolutionary potential and management of corals in response to climate change. In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2019) was used to compute a complete and consistent set of carbonate system variables, as described by Nisumaa et al. (2010). In this dataset the original values were archived in addition with the recalculated parameters (see related PI). The date of carbonate chemistry calculation by seacarb is 2020-05-6.

Agriculture is a critical component of the human food system. Its coupling to the success of human societies and its impact on the environment is nontrivial. Varied efforts -- including new regulations, certifications, techniques and software -- exist to assess and improve the sustainability of agriculture. Multiple stakeholders in a fragmented field, with tensions and pulls in different directions, results in a duplication of efforts and disconnected data and processes.To explore the challenges that exist in modeling sustainable agriculture, I characterize environmental assessment as a modeling process, and secondly, characterize sustainable agricultural systems as a type of complex adaptive system. Framing the assessment process and system of interest in this manner permits the application of various techniques from software engineering, systems analysis, and human-computer interaction to tease apart the core issues and to subsequently respond to these challenges through design.First, I present an analysis of the capacity of Life Cycle Assessment (a formal and quantitative environmental assessment technique) to represent small- to medium-scale sustainability-oriented farms. Then, I described a qualitative field study, in which I visited 16 farms across California, interviewing sustainability-oriented farmers, and collecting samples of farm data. The goal of this study was to uncover how and why farmers model farms in practice, the nature and availability of farm data, and the experiences of farmers with various environmental assessment techniques.The findings of these two studies resulted in the articulation of domain-specific modeling requirements. These include: creating selective and partial system models, knitting together qualitative and quantitative data in system models, capturing both spatial and temporal structures, and all of this through models that are abstract yet grounded in real farm data.Building on these studies, I present MoSS: a framework to enable the Modeling of Sustainable Systems. MoSS consists of three parts: an abstract model, domain-specific elements to allow for modeling agricultural systems, and model 'perspectives' that allow for the assessment of the environmental performance of the system. I conducted a scenario-based evaluation of MoSS to assess its ability to express the varying dynamism and complexity of sustainable agricultural systems. MoSS addresses the core challenges involved in modeling sustainable agriculture, providing a consistent mechanism to capture the essence of farms.MoSS represents a step forward in grounded information design for sustainable agriculture, paving the way for the design of information management and environmental assessment tools that more closely meet the needs of small- to medium-scale farms and farmers. Through the work presented in this dissertation, I have also demonstrated how one may engage in applied and interdisciplinary software engineering research to support sustainable development.

Uncertainty about compliance costs causes otherwise equivalent price and quantity controls to behave differently. Price controls - in the form of taxes - fix the marginal cost of compliance and lead to uncertain levels of compliance. Meanwhile quantity controls - in the form of tradable permits or quotas - fix the level of compliance but result in uncertain marginal costs. This fundamental difference in the face of cost uncertainty leads to different welfare outcomes for the two policy instruments. Seminal work by Weitzman (1974) clarified this point and derived theoretical conditions under which one policy is preferred to the other. This paper applies this principal to the issue of worldwide greenhouse gas (GHG) control, using a global integrated climate economy model to simulate the consequences of uncertainty and to compare the efficiency of taxes and permits empirically. The results indicate that an optimal tax policy generates gains which are five times higher than the optimal permit policy - a $337 billion dollar gain versus $69 billion at the global level. This result follows from Weitzman's original intuition that relatively flat marginal benefits/damages favor taxes, a feature that drops out of standard assumptions about the nature of climate damages. A hybrid policy, suggested by Roberts and Spence (1976), is also explored. Such a policy uses an initial distribution of tradeable permits to set a target emission level, but then allows additional permits to be purchased at a fixed "trigger" price. The optimal hybrid policy leads to welfare benefits only slightly higher than the optimal tax policy. Relative to the tax policy, however, the hybrid preserves the ability to flexibly distribute the rents associated with the right to emit. Perhaps more importantly for policy discussions, a sub-optimal hybrid policy, based on a stringent target and high trigger price (e.g., 1990 emissions and a $100/tC trigger), generates much better welfare outcomes than a straight permit system with the same target. Both of these features suggest that a hybrid policy is a more attractive alternative to either a straight tax or permit system.

In Arizona, the policy debates over the Colorado River Basin Drought Contingency Plans exposed longrunning tensions surrounding how we use and value scarce water resources in a desert. These negotiations also highlighted generations-old disputes between indigenous communities’ water rights and Anglo settlers. This paper explores how irrigators respond to, and participate in, the crafting of institutional arrangements while at the same time experiencing increased exposure to climatic and hydrological risk. Our analysis incorporates qualitative interview data, a literature review, archival information from policy reports, and secondary data on water use and agricultural production. Building on the fieldwork with farmers and water experts that we completed before the drought contingency planning efforts began, we describe the status quo and then explore potential future contexts based on shifting incentives and on the constraints that arise during periods of Colorado River water shortages. Through an understanding of the socio-hydrological system, we examine the region’s agricultural water use, water governance, indigenous water rights and co-governance, and the potential future of agriculture in the region. Our study illustrates how the historic and current institutions have been maintaining agricultural vibrancy but also creating new risks associated with increased dependence on the Colorado River.

The Ice Sheet Model Intercomparison Project for CMIP6 (ISMIP6) brings together a consortium of international ice-sheet and climate modellers to simulate the contribution from the Greenland and Antarctic ice sheets to future sea-level rise. In this document, we describe the set-up and main results of the ISMIP6 Antarctica Tier-1 and Tier-2 experiments carried out with the ice-sheet model SICOPOLIS. The companion document for the Greenland ice sheet is available at https://doi.org/10.5281/zenodo.3971251. V1.0.1: References updated; some minor corrections. V1: Full report. V0.1: Abstract only. Funding acknowledgements: Japan Society for the Promotion of Science (JSPS) KAKENHI grant Nos. JP16H02224, JP17H06104 and JP17H06323. PalMod project (PalMod 1.1 and 1.3 with grants 01LP1502C and 01LP1504D) of the German Federal Ministry of Education and Research (BMBF).

The Forward Search Experiment (FASER) at CERN’s Large Hadron Collider (LHC) has recently directly detected the first collider neutrinos. Neutrinos play an important role in all FASER analyses, either as signal or background, and it is therefore essential to understand the neutrino event rates. In this study, we update previous simulations and present prescriptions for theoretical predictions of neutrino fluxes and cross sections, together with their associated uncertainties. With these results, we discuss the potential for possible measurements that could be carried out in the coming years with the FASER neutrino data to be collected in LHC Run 3 and Run 4. Physical review / D 110(1), 012009 (2024). doi:10.1103/PhysRevD.110.012009 Published by American Physical Society, Ridge, NY