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A clearer view of systematic errors in model development: two practical approaches using perturbed parameter ensemblesNARA Subscribed
Models of weather and climate are continuously being developed to improve their reliability and, ultimately, to help users make more informed decisions. But they are often affected by inadequacies in the physical approximations they use, which can lead to ‘systematic’ errors. Exposing, understanding, and resolving these errors is therefore a key aim of model development. One technique that can readily expose systematic errors...
The northwest European shelf (NWS) seas are environmentally and economically important, and an understanding of how their climate may change helps with their management. However, as the NWS seas are poorly represented in global climate models, a common approach is to dynamically downscale with an appropriate shelf sea model. We develop a set of physical marine climate projections for the NWS. We dynamically downscale 12 member...
Prediction of slowdown of the Atlantic Meridional Overturning Circulation in coupled model simulationsNARA Subscribed
In coupled perturbed parameter ensemble (PPE) experiments or for development of a single coupled global climate model (GCM) in general, models can exhibit a slowdown in the Atlantic Meridional Overturning Circulation (AMOC) that can result in unrealistically reduced transport of heat and other tracers. Here we propose a method that researchers running PPE experiments can apply to their own PPE to diagnose what controls the AMO...
Describing future UK winter precipitation in terms of changes in local circulation patternsNARA Subscribed
Social scientists have argued that good communication around risks in climate hazards requires information to be presented in a user-relevant way, allowing people to better understand the factors controlling those risks. We present a potentially useful way of doing this by explaining future UK winter precipitation in terms of changes in the frequency, and associated average rainfall, of local pressure patterns that people are...
Evaluation and projections of the East Asian summer monsoon in a perturbed parameter ensembleNARA Subscribed
The East Asian summer monsoon (EASM) is a dominant driver of East Asian climate, with variations in its strength potentially impacting the livelihoods of millions of people. Understanding, predicting, and assessing uncertainties in these variations are therefore important area of research. Here, we present a study of the projected twenty-first century changes in the EASM using a ‘perturbed parameter ensemble’ (PPE) of HadGEM3-...
The National Oceanic and Atmospheric Administration (NOAA) Living Marine Resources Cooperative Science Center (LMRCSC) was established in 2001 as a multi-institutional collaborative program with the goal of preparing a diverse future STEM workforce in marine and fisheries sciences. Using best practices for recruiting, mentoring, and training students, the Center has had a significant impact on the number of individuals from un...
Prolonging survival in good health is a fundamental societal goal. However, the leading determinants of disability-free survival in healthy older people have not been well established. Data from ASPREE, a bi-national placebo-controlled trial of aspirin with 4.7 years median follow-up, was analysed. At enrolment, participants were healthy and without prior cardiovascular events, dementia or persistent physical disability. Disab...
Potential shifts in climate zones under a future global warming scenario using soil moisture classificationNARA Subscribed
Climate zones fundamentally shape the patterns of the terrestrial environment and human habitation. How global warming alters their current distribution is an important question that has yet to be properly addressed. Using root-layer soil moisture as an indicator, this study investigates potential future changes in climate zones with the perturbed parameter ensemble of climate projections by the HadGEM3-GC3.05 model under the...
The impact of performance filtering on climate feedbacks in a perturbed parameter ensembleNARA Subscribed
A key contribution to the latest generation of climate projections for the UK (UKCP18) was a perturbed parameter ensemble (PPE) of global coupled models based on HadGEM3-GC3.05. Together with 13 CMIP5 simulations, this PPE provides users with a dataset that samples modelling uncertainty and is ideal for use in impacts studies. Evaluations of global mean surface temperatures for this PPE have shown twenty-first century warming...
Climate and land‐use change are the major drivers of global biodiversity loss. Their effects are particularly acute for wide‐ranging consumers, but little is known about how these factors interact to affect the abundance of large carnivores and their herbivore prey. We analyzed population densities of a primary and secondary consumer (mule deer, Odocoileus hemionus , and mountain lion, Puma concolor ) across a climatic gradien...
Climate structures genetic variation across a species' elevation range: a test of range limits hypothesesNARA Subscribed
Gene flow may influence the formation of species range limits, and yet little is known about the patterns of gene flow with respect to environmental gradients or proximity to range limits. With rapid environmental change, it is especially important to understand patterns of gene flow to inform conservation efforts. Here we investigate the species range of the selfing, annual plant, Mimulus laciniatus , in the California Sierra...