Use Of Climate Projections Research Articles

Improving access and use of climate projections for ecological research through the use of a new Python tool

Over the past decade, the use of future climate projections from the coupled model intercomparison project (CMIP) has become central in biodiversity science. Pre‐packaged datasets containing future projections of the widely used bioclimatic variables, for different times and socio‐economic pathways, have contributed immensely to the study of climate change implications for biodiversity. However, these datasets lack the flexibility to obtain projections to other target years, and the use of raw data requires coding and spatial information systems expertise. The Python tool, ‘chelsa‐cmip6', developed by Karger et al., provides the flexibility needed by allowing users to generate bioclimatic variables for the time of their choice provided the selected general circulation model and socioeconomic pathway combination exists. This is a fantastic step forward in bringing flexibility to the use of climate datasets in biodiversity and will allow for more widespread use of data provided by CMIP6. We hope it also will prompt the development of more user‐friendly tools for the study of the effects of climate change on biodiversity.

Comparing established practice for short-term forecasts and emerging use of climate projections to identify opportunities for climate services in Australian agriculture

The use of climate services in agriculture to improve both tactical and strategic management decisions on farm is an area of increasing societal interest and technological development in Australia, as climate change increases climate variability and risk. Yet the focus of most uses of climate services remains on weather and seasonal forecasts and tactical farm responses, with longer term climate projections less often empirically examined. In this paper we analyse 25 interviews with farmers in Australia and use social practice theory to compare farm risk management decisions utilising short-term weather forecasting and longer-term climate projection planning. We identify different elements of climate risk management as a social practice, looking particularly at materials (objects and tools), meanings (beliefs and thinking) and competencies (skills and knowledge) associated with climate services. We find that there are significant differences in how decisions are made using different temporal data scales and furthermore, that there are large gaps in the materials, meaning and competencies for the use of longer-term climate projections. This analysis allows us to clearly identify opportunities for the agricultural sector in Australia, and globally, to better support decisions in both weather and climate timeframes by treating these as distinctly different capabilities and addressing the different elements of social practice outlined here.

Assessing sensitivities of climate model weighting to multiple methods, variables, and domains in the south-central United States

Abstract. Given the increasing use of climate projections and multi-model ensemble weighting for a diverse array of applications, this project assesses the sensitivities of climate model weighting strategies and their resulting ensemble means to multiple components, such as the weighting schemes, climate variables, or spatial domains of interest. The purpose of this study is to assess the sensitivities associated with multi-model weighting strategies. The analysis makes use of global climate models from the Coupled Model Intercomparison Project Phase 5 (CMIP5) and their statistically downscaled counterparts created with the localized constructed analogs (LOCA) method. This work focuses on historical and projected future mean precipitation and daily high temperatures of the south-central United States. Results suggest that the model weights and the corresponding weighted model means can be sensitive to the weighting strategy that is applied. For instance, when estimating model weights based on Louisiana precipitation, the weighted projections show a wetter and cooler south-central domain in the future compared to other weighting strategies. Alternatively, for example, when estimating model weights based on New Mexico temperature, the weighted projections show a drier and warmer south-central domain in the future. However, when considering the entire south-central domain in estimating the model weights, the weighted future projections show a compromise in the precipitation and temperature estimates. As for uncertainty, our matrix of results provided a more certain picture of future climate compared to the spread in the original model ensemble. If future impact assessments utilize weighting strategies, then our findings suggest that how the specific weighting strategy is used with climate projections may depend on the needs of an impact assessment or adaptation plan.

Looking to the (far) future of climate projection.

The use of climate projections is important in determining Earth's future and our place in it. These projections inform policy, both at the country scale, and globally, assisting leaders in their commitment to various pledges of mitigation in an attempt to prevent further climate change in the future and maybe even reverse it. The Intergovernmental Panel on Climate Change (IPCC) release periodic 'Assessment Reports' which provide a current state of the climate and climate projections from modelling centres.

Communicating future climate projections of precipitation change

Understanding how precipitation may change in the future is important for guiding climate change adaptation. Climate models are the primary tools for providing information on future precipitation change, though communicating and interpreting results of different model simulations is challenging. Using an online survey, completed by producers and users of climate model information, we compare and evaluate interpretations of different approaches used to summarise and visualise future climate projections. Results reveal large differences in interpretations of precipitation change arising from choices made in summarising and visualising the data. Respondents interpret significantly smaller ranges of future precipitation change when provided with the multi-model ensemble mean or percentile information, which are commonly used to summarise climate model projections, compared to information about the full ensemble. The ensemble mean is found to be particularly misleading, even when used with information to show model agreement in the sign of change. We conclude that these approaches can lead to distorted interpretations which may impact on adaptation policy and decision-making. To help improve the interpretation and use of climate projections in decision-making, regular testing of visualisations and sustained engagement with target audiences is required to determine the most effective and appropriate visualisation approaches.

A climate projection dataset tailored for the European energy sector

Climate information is necessary for the energy sector. However, the use of climate projections has remained limited so far for a number of reasons such us the lack of consistency among climate projections, the inadequate temporal and spatial resolution, the climate model biases, the lack of guidance for users, and the size of data sets. In this work, we develop and assess a consistent ensemble of high time and space resolution climate projections that address these problems. First, a methodology for sub-ensemble selection is developed and proposed. Our ensemble dataset includes eleven 12 km-resolution EURO-CORDEX simulations of temperature, precipitation, wind speed and surface solar radiation on 3-hourly and daily time scales. These variables are bias-corrected for a more effective use into impact studies. The assessment of bias-corrected model simulations against observational data indicates reduced biases and increased coherence in projected changes among models compared to the raw climate projections. We provide a well-documented dataset for energy practitioners and decision-makers to facilitate the access and use of energy-relevant high-quality climate information in operation and planning. The new dataset is freely available via the Earth System Grid Federation (ESGF) platform.

\u2018Eastern African Paradox\u2019 rainfall decline due to shorter not less intense Long Rains

An observed decline in the Eastern African Long Rains from the 1980s to late 2000s appears contrary to the projected increase under future climate change. This “Eastern African climate paradox” confounds use of climate projections for adaptation planning across Eastern Africa. Here we show the decline corresponds to a later onset and earlier cessation of the long rains, with a similar seasonal maximum in area-averaged daily rainfall. Previous studies have explored the role of remote teleconnections, but those mechanisms do not sufficiently explain the decline or the newly identified change in seasonality. Using a large ensemble of observations, reanalyses and atmospheric simulations, we propose a regional mechanism that explains both the observed decline and the recent partial recovery. A decrease in surface pressure over Arabia and warmer north Arabian Sea is associated with enhanced southerlies and an earlier cessation of the long rains. This is supported by a similar signal in surface pressure in many atmosphere-only models giving lower May rainfall and an earlier cessation. Anomalously warm seas south of Eastern Africa delay the northward movement of the tropical rain-band, giving a later onset. These results are key in understanding the paradox. It is now a priority to establish the balance of mechanisms that have led to these trends, which are partially captured in atmosphere-only simulations.

Impact of choice of future climate change projection on growth chamber experimental outcomes: a preliminary study in potato.

Understanding the impacts of climate change on agriculture is essential to ensure adequate future food production. Controlled growth experiments provide an effective tool for assessing the complex effects of climate change. However, a review of the use of climate projections in 57 previously published controlled growth studies found that none considered within-season variations in projected future temperature change, and few considered regional differences in future warming. A fixed, often arbitrary, temperature perturbation typically was applied for the entire growing season. This study investigates the utility of employing more complex climate change scenarios in growth chamber experiments. A case study in potato was performed using three dynamically downscaled climate change projections for the mid-twenty-first century that differ in terms of the timing during the growing season of the largest projected temperature changes. The climate projections were used in growth chamber experiments for four elite potato cultivars commonly planted in Michigan's major potato growing region. The choice of climate projection had a significant influence on the sign and magnitude of the projected changes in aboveground biomass and total tuber count, whereas all projections suggested an increase in total tuber weight and a decrease in specific gravity, a key market quality trait for potato, by mid-century. These results demonstrate that the use of more complex climate projections that extend beyond a simple incremental change can provide additional insights into the future impacts of climate change on crop production and the accompanying uncertainty.

Robustness-based evaluation of hydropower infrastructure design under climate change

The conventional tools of decision-making in water resources infrastructure planning have been developed for problems with well-characterized uncertainties and are ill-suited for problems involving climate nonstationarity. In the past 20years, a predict-then-act-based approach to the incorporation of climate nonstationarity has been widely adopted in which the outputs of bias-corrected climate model projections are used to evaluate planning options. However, the ambiguous nature of results has often proved unsatisfying to decision makers. This paper presents the use of a bottom-up, decision scaling framework for the evaluation of water resources infrastructure design alternatives regarding their robustness to climate change and expected value of performance. The analysis begins with an assessment of the vulnerability of the alternative designs under a wide domain of systematically-generated plausible future climates and utilizes downscaled climate projections ex post to inform likelihoods within a risk-based evaluation. The outcomes under different project designs are compared by way of a set of decision criteria, including the performance under the most likely future, expected value of performance across all evaluated futures and robustness. The method is demonstrated for the design of a hydropower system in sub-Saharan Africa and is compared to the results that would be found using a GCM-based, scenario-led analysis. The results indicate that recommendations from the decision scaling analysis can be substantially different from the scenario-led approach, alleviate common shortcomings related to the use of climate projections in water resources planning, and produce recommendations that are more robust to future climate uncertainty.

Adaptation planning and the use of climate change projections in local government in England and Germany

Planning for adaptation to climate change is often regarded to be a local imperative and considered to be more effective if grounded on a solid evidence base and recognisant of relevant climate projections. Research has already documented some of the challenges of making climate information usable in decision-making but has not yet sufficiently reflected on the role of the wider institutional and regulatory context. This article examines the impact of the external institutional context on the use and usability of climate projections in local government through an analysis of 44 planning and climate change (adaptation) documents and 54 semi-structured interviews with planners in England and Germany conducted between July 2013 and May 2014. We show that there is little demand for climate projections in local adaptation planning in either country due to existing policy, legal and regulatory frameworks. Local government in England has not only experienced a decline in use of climate projections, but also the waning of the climate change adaptation agenda more widely, amidst changes in the planning and regulatory framework and severe budget cuts. In Germany, spatial planning makes substantial use of past and present climate data, but the strictly regulated nature of planning prevents the use of climate projections, due to their inherent uncertainties. Findings from the two countries highlight that if we are to better understand the usability of climate projections, we need to be more aware of the institutional context within which planning decisions are made. Otherwise we run the risk of continuing to provide tools and information that are of limited use within their intended context.

Assessing the Resilience of LEED Certified Green Buildings

The Leadership in Energy & Environmental Design (LEED) green building certification program is dedicated to the design of sustainable buildings by incentivizing reductions in energy, water, and building materials consumption, while at the same time enhancing occupant health and overall community connectivity. While green buildings certified by the program do reduce the environmental footprint of buildings, they must also be designed for resilience to withstand external stressors that may arise over the buildings’ lifetime for it to be truly sustainable. Therefore, a resilient building should be able to adapt and remain functional while under pressure from more frequent and severe climatic events. The goal of the study was to analyze existing inherent overlaps between resilient design principles and the LEED certification system. Synergistic opportunities together with improvements for better integrating resilient design into the LEED checklist, and hence green buildings, by modifying existing or proposing new credits were discussed. The use of climate projections instead of historical climate data during design was recommended. Regional priority credits need to be specified further to address the unique regional needs of each project to improve resilience in light of a particular region's future climate outlook.

Towards a dedicated impact portal to bridge the gap between the impact and climate communities : Lessons from use cases

Future climate evolution is of primary importance for the societal, economical, political orientations and decision-making. It explains the increasing use of climate projections as input for quantitative impact studies, assessing vulnerability and defining adaptation strategies in different sectors. Here we analyse 17 national and representative use cases so as to identify the diversity of the demand for climate information depending on user profiles as well as the best practices, methods and tools that are needed to answer the different requests. A particular emphasis is put on the workflow that allows to translate climate data into suitable impact data, the way to deal with the different sources of uncertainty and to provide a suited product to users. We identified three complementary tools to close the gap between climate scientists and user needs: an efficient interface between users and providers; an optimized methodology to handle user requests and a portal to facilitate access to data and elaborated products. We detail in the paper how these three tools can limit the intervention of experts, educate users, and lead to the production of useful information. This work provides the basis on which the ENES (European Network for Earth System Modelling) Portal Interface for the Climate Impact Communities is built.

Climate change in California: scenarios and approaches for adaptation

Even with aggressive global action to reduce greenhouse gas emissions, the climate will continue to change for decades due to previous emissions and the inertia in biogeophysical and social systems. Therefore, as a complement to mitigation actions, society must also focus on enhancing its capacity to adapt to the unavoidable impacts of climate change that we are already experiencing and will continue to experience over the next few decades. Resource managers, regional planners, and government agencies need to consider climate risks in their planning. We provide an overview of climate change scenarios for California and suggestions on the use of climate projections in state and regional planning efforts in the future.

A framework for assessing flood frequency based on climate projection information

Abstract. Flood safety is of the utmost concern for water resources management agencies charged with operating and maintaining reservoir systems. Risk evaluations guide design of infrastructure alterations or lead to potential changes in operations. Changes in climate may change the risk due to floods and therefore decisions to alter infrastructure with a life span of decades or longer may benefit from the use of climate projections as opposed to use of only historical observations. This manuscript presents a set of methods meant to support flood frequency evaluation based on current downscaled climate projections and the potential implications of changing flood risk on how evaluations are made. Methods are demonstrated in four case study basins: the Boise River above Lucky Peak Dam, the San Joaquin River above Friant Dam, the James River above Jamestown Dam, and the Gunnison River above Blue Mesa Dam. The analytical design includes three core elements: (1) a rationale for selecting climate projections to represent available climate projections; (2) generation of runoff projections consistent with climate projections using a process-based hydrologic model and temporal disaggregation of monthly downscaled climate projections into 6-h weather forcings required by the hydrologic model; and (3) analysis of flood frequency distributions based on runoff projection results. In addition to demonstrating the methodology, this paper also presents method choices under each analytical element, and the resulting implications to how flood frequencies are evaluated. The methods used reproduce the antecedent calibration period well. The approach results in a unidirectional shift in modeled flood magnitudes. The comparison between an expanding retrospective (current paradigm for flood frequency estimation) and a lookahead flood frequency approach indicate potential for significant biases in flood frequency estimation.

Review of scenario selection and downscaling methods for the assessment of climate change impacts on hydrology in the United States pacific northwest

AbstractThis paper reviews methods that have been used to evaluate global climate simulations and to downscale global climate scenarios for the assessment of climate impacts on hydrologic systems in the Pacific Northwest, USA. The approach described has been developed to facilitate integrated assessment research in support of regional resource management. Global climate model scenarios are evaluated and selected based on historic 20th century simulations. A statistical downscaling method is then applied to produce a regional data set. To facilitate the use of climate projections in hydrologic assessment, additional statistical mapping may be applied to generate synthetic station time series. Finally, results are presented from a regional climate model that indicate important differences in the regional climate response from what is captured by global models and statistical downscaling. Copyright © 2007 Royal Meteorological Society