The role of the simulation setup in a long-term high-resolution climate change projection for the southern African region

2011 ◽  
Vol 106 (1-2) ◽  
pp. 153-169 ◽  
Author(s):  
Andreas Haensler ◽  
Stefan Hagemann ◽  
Daniela Jacob
Keyword(s):  
Climate Change ◽  
High Resolution ◽  
African Region ◽  
Climate Change Projection ◽  
Southern African Region

scholarly journals Lyell, the Geikies and Croll's observations on terrestrial glacial sediments and landforms

2021 ◽  
pp. 1-14
Author(s):  
James ROSE
Keyword(s):  
Climate Change ◽  
High Quality ◽  
Glacial Sediments ◽  
Direct Observations ◽  
The Social ◽  
The Status ◽  
Social And Physical Environment ◽  
Glacial Landforms

ABSTRACT Within the context of the work and achievements of James Croll, this paper reviews the records of direct observations of glacial landforms and sediments made by Charles Lyell, Archibald and James Geikie and James Croll himself, in order to evaluate their contributions to the sciences of glacial geology and Quaternary environmental change. The paper outlines the social and physical environment of Croll's youth and contrasts this with the status and experiences of Lyell and the Geikies. It also outlines the character and role of the ‘Glasgow School’ of geologists, who stimulated Croll's interest into the causes of climate change and directed his focus to the glacial and ‘interglacial’ deposits of central Scotland. Contributions are outlined in chronological order, drawing attention to: (i) Lyell's high-quality observations and interpretations of glacial features in Glen Clova and Strathmore and his subsequent rejection of the glacial theory in favour of processes attributed to floating icebergs; (ii) the significant impact of Archibald Geikie's 1863 paper on the ‘glacial drift of Scotland’, which firmly established the land-ice theory; (iii) the fact that, despite James Croll's inherent dislike of geology and fieldwork, he provided high-quality descriptions and interpretations of the landforms and sediments of central Scotland in order to test his theory of climate change; and (iv) the great communication skills of James Geikie, enhanced by contacts and evidence from around the world. It is concluded that whilst direct observations of glacial landforms and sediments were critical to the long-term development of the study of glaciation, the acceptance of this theory was dependent also upon the skills, personality and status of the Geikies and Croll, who developed and promoted the concepts. Sadly, the subsequent rejection of the land-ice concept by Lyell resulted in the same factors challenging the acceptance of the glacial theory.

Impact and uncertainty of climate projections on Alpine catchments using high-resolution models

2021 ◽  
Author(s):  
Jorge Sebastian Moraga ◽  
Nadav Peleg ◽  
Simone Fatichi ◽  
Peter Molnar ◽  
Paolo Burlando
Keyword(s):  
Climate Change ◽  
High Resolution ◽  
Climate Variability ◽  
Soil Conditions ◽  
Internal Climate Variability ◽  
Mountainous Catchments ◽  
Precipitation Decrease ◽  
Alpine Catchments ◽  
Impacts Of Climate Change

<p>Hydrological processes in mountainous catchments will be subject to climate change on all scales, and their response is expected to vary considerably in space. Typical hydrological studies, which use coarse climate data inputs obtained from General Circulation Models (GCM) and Regional Climate Models (RCM), focus mostly on statistics at the outlet of the catchments, overlooking the effects within the catchments. Furthermore, the role of uncertainty, especially originated from natural climate variability, is rarely analyzed. In this work, we quantified the impacts of climate change on hydrological components and determined the sources of uncertainties in the projections for two mostly natural Swiss alpine catchments: Kleine Emme and Thur. Using a two-dimensional weather generator, AWE-GEN-2d, and based on nine different GCM-RCM model chains, we generated high-resolution (2 km, 1 hour) ensembles of gridded climate inputs until the end of the 21<sup>st</sup> century. The simulated variables were subsequently used as inputs into the fully distributed hydrological model Topkapi-ETH to estimate the changes in hydrological statistics at 100-m and hourly resolutions. Increased temperatures (by 4°C, on average) and changes in precipitation (decrease over high elevations by up to 10%, and increase at the lower elevation by up to 15%) results in increased evapotranspiration rates in the order of 10%, up to a 50% snowmelt, and drier soil conditions. These changes translate into important shifts in streamflow seasonality at the outlet of the catchments, with a significant increase during the winter months (up to 40%) and a reduction during the summer (up to 30%). Analysis at the sub-catchment scale reveals elevation-dependent hydrological responses: mean annual streamflow, as well as high and low flow extremes, are projected to decrease in the uppermost sub-catchments and increase in the lower ones. Furthermore, we computed the uncertainty of the estimations and compared them to the magnitude of the change signal. Although the signal-to-noise-ratio of extreme streamflow for most sub-catchments is low (below 0.5) there is a clear elevation dependency. In every case, internal climate variability (as opposed to climate model uncertainty) explains most of the uncertainty, averaging 85% for maximum and minimum flows, and 60% for mean flows. The results highlight the importance of modelling the distributed impacts of climate change on mountainous catchments, and of taking into account the role of internal climate variability in hydrological projections.</p>

Physiological and morphological effects of climate change

2019 ◽  
pp. 120-133 ◽  
Author(s):  
Andrew E. McKechnie
Keyword(s):  
Climate Change ◽  
Body Mass ◽  
High Temperatures ◽  
Arid Zone ◽  
Future Research ◽  
Long Term Effects ◽  
Adaptation To Climate Change ◽  
Heat Events

The direct impacts of higher temperatures on birds are manifested over timescales ranging from minutes and hours to years and decades. Over short timescales, acute exposure to high temperatures can lead to hyperthermia or dehydration, which among arid-zone species occasionally causes catastrophic mortality events. Over intermediate timescales of days to weeks, high temperatures can have chronic sub-lethal effects via body mass loss or reduced nestling growth rates, negatively affecting sev eral fitness components. Long-term effects of warming manifested over years to decades involve declining body mass or changes in appendage size. Key directions for future research include elucidating the role of phenotypic plasticity and epigenetic processes in avian adaptation to climate change, examining the role of stress pathways in mediating responses to heat events, and understanding the consequences of higher temperatures for species that traverse hot regions while migrating.

scholarly journals Bridging worlds: community led visual methods amidst climate change related disasters in Australia

2019 ◽  
Vol 29 (Supplement_4) ◽  
Author(s):  
C Macdougall ◽  
L Gibbs
Keyword(s):  
Climate Change ◽  
Rural Communities ◽  
Service Providers ◽  
Natural Environments ◽  
Visual Methods ◽  
Community Recovery ◽  
Visual Record ◽  
And Control

Abstract Background In February 2009 Victorian rural communities were hit by the worst bushfires in Australian history. Immediately we evaluated community groups preparing residents for bushfires. Ten years on, we are one of the few teams to evaluate medium to long term community recovery using multiple methods. As climate change becomes more visible, the frequency and intensity of disasters will increase so communities, governments and service providers need more evidence based strategies and policies. We explore how participant led visual methods provide new knowledge. Methods In study 1 participants in 3 of 7 focus groups in peoples’ homes spontaneously brought photos for us to examine before the discussions. In another participants spoke of the importance of photos they took at the time. We returned to the field to interview people in their homes about the meaning and role of photos. Results Participants wanted to inform us-as outsiders-of the awe and enormity of the fires. They created a visual record to communicate with key interest groups and ward off complacity as memories receded. Photos helped them construct timelines and meanings of the intense fires. Crucially, they recorded recovery and rebuilding in both the built and natural environments. Over the next ten years we chronicled stories from community led visual methods of communication, recovery and empowerment. We incorporated into qualitative methods participant led tours of their environments, with visual methods. Visual data collected by communities focused more strongly on the natural environment than researcher led verbal methods. Conclusions Visual sociology changes as technology provides participants in research with increased access to, and control over, visual methods. These changes can rebalance power relations between qualitative researchers and participants and bridge visual and verbal methods; crafting striking stories to influence those Australian policies unresponsive to climate change. Key messages Technological change enables participants in qualitative research to initiate visual methods to build bridges between them and researchers. Community led visual methods provide new types of data useful for theory and knowledge translation.

Solar futures: a systematic review of long-term global solar photovoltaic adoption scenarios

2020 ◽  
Author(s):  
Marc Jaxa-Rozen ◽  
Evelina Trutnevyte
Keyword(s):  
Climate Change ◽  
Renewable Energy ◽  
Solar Photovoltaic ◽  
Energy Access ◽  
Solar Pv ◽  
Global Energy ◽  
Energy Transitions ◽  
Term Energy

<p>Solar photovoltaic (PV) technology has been the fastest-growing renewable energy technology in recent years. Since 2009, it has in fact experienced the largest capacity growth of any power generation technology, with benchmark levelized costs falling by four-fifths [1]. In addition, the global technical potential of PV largely exceeds global primary energy demand [2]. Nonetheless, PV typically only appears as a relatively marginal option in long-term energy modelling studies and scenarios. These include the mitigation pathways evaluated in the context of the work of the Intergovernmental Panel on Climate Change (IPCC), which rely on integrated assessment models (IAMs) of climate change and have in the past underestimated PV growth as compared to observed rates of adoption [2]. Similarly, global energy projections, such as the International Energy Agency's World Energy Outlook, have been relatively conservative regarding the role of solar PV in long-term energy transitions.</p><p>In order to better understand the long-term global role of solar PV as perceived by various modeling communities, this work synthesizes a broad ensemble of scenarios for global PV adoption at the 2050 horizon. This ensemble includes 784 IAM-based scenarios from the IPCC SR15 and AR5 databases, and 82 other systematically selected scenarios published over the 2010-2019 period in the academic and gray literature, such as PV-focused techno-economic analyses and global energy outlooks. The scenarios are analyzed using a descriptive framework which combines scenario indicators (e.g. mitigation policies depicted in a scenario), model indicators (e.g. the representation of technological change in the underlying model), and meta-indicators (e.g. the type of institution which authored a scenario). We extend this scenario framework to include a text-mining approach, using Latent Dirichlet Allocation (LDA) to associate scenarios with different textual perspectives identified in the ensemble, such as energy access or renewable energy transitions. We then use a scenario discovery approach to identify the combinations of indicators which are most strongly associated with different regions of the scenario space.</p><p>Preliminary results indicate that the date of publication of a scenario has a predominant influence on projected PV adoption values: scenarios published in the first half of the 2010s thus tend to represent considerably lower PV adoption levels. In parallel, higher projected values are more strongly associated with renewable-focused institutions. Increasing the institutional diversity of scenario ensembles may thus lead to a broader range of considered futures [3].</p><p> <br>References<br>[1] Frankfurt School-UNEP Centre, “Global Trends in Renewable Energy Investment 2019,” Frankfurt, Germany, 2019.<br>[2] F. Creutzig, P. Agoston, J. C. Goldschmidt, G. Luderer, G. Nemet, and R. C. Pietzcker, “The underestimated potential of solar energy to mitigate climate change,” Nat Energy, vol. 2, no. 9, pp. 1–9, Aug. 2017, doi: 10.1038/nenergy.2017.140.<br>[3] E. Trutnevyte, W. McDowall, J. Tomei, and I. Keppo, “Energy scenario choices: Insights from a retrospective review of UK energy futures,” Renewable and Sustainable Energy Reviews, vol. 55, pp. 326–337, Mar. 2016, doi: 10.1016/j.rser.2015.10.067.</p>

scholarly journals Energy efficiency, resilience to future climates and long-term sustainability: the role of the built environment

2010 ◽  
Vol 368 (1914) ◽  
pp. 1083-1089 ◽  
Author(s):  
M. J. Kelly
Keyword(s):  
Climate Change ◽  
Energy Efficiency ◽  
Energy Consumption ◽  
Built Environment ◽  
Energy Security ◽  
Sustainable Consumption ◽  
Existing Buildings ◽  
The Uk

Just under half of all energy consumption in the UK today takes place indoors, and over a quarter within our homes. The challenges associated with energy security, climate change and sustainable consumption will be overcome or lost in our existing buildings. A background analysis, and the scale of the engineering challenge for the next three to four decades, is described in this paper.

scholarly journals On the Role of Radiative Processes in Stratosphere–Troposphere Coupling

2009 ◽  
Vol 22 (15) ◽  
pp. 4154-4161 ◽  
Author(s):  
Kevin M. Grise ◽  
David W. J. Thompson ◽  
Piers M. Forster
Keyword(s):  
Climate Change ◽  
Temperature Response ◽  
Longwave Radiation ◽  
Tropospheric Temperature ◽  
Radiative Processes ◽  
Ozone Trends ◽  
Radiation Induced ◽  
Polar Stratosphere

Abstract Climate change in the Southern Hemisphere (SH) polar stratosphere is associated with substantial changes in the atmospheric circulation that extend to the earth’s surface. The mechanisms that drive the changes in the SH troposphere are not fully understood, but most previous hypotheses have focused on the role of atmospheric dynamics rather than that of radiation. This study quantifies the radiative response of temperatures in the SH polar troposphere to the forcing from long-term temperature and ozone trends in the SH polar stratosphere. A novel methodology is employed that explicitly neglects changes in tropospheric dynamics and hence isolates the component of the tropospheric temperature response that is radiatively driven by the overlying stratospheric trends. The results reveal that both the amplitude and seasonality of the observed cooling of the middle and upper SH polar troposphere over the past few decades are consistent with a reduction in downwelling longwave radiation induced by cooling in the SH polar stratosphere. The results are compared with analogous calculations for trends in the Northern Hemisphere (NH) polar stratosphere. Both the observations and radiative calculations imply that the comparatively weak trends in the NH polar stratosphere have not played a central role in driving NH tropospheric climate change. Overall, the results suggest that radiative processes play a key role in coupling the large trends in SH polar stratospheric temperatures to tropospheric levels. The tropospheric radiative temperature response documented here could be important for triggering the changes in internal tropospheric dynamics associated with stratosphere–troposphere coupling.

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