Top PDF Regional Geographies of Extreme Heat

Regional Geographies of Extreme Heat

Regional Geographies of Extreme Heat

patterns. And these regional-to-local patterns and processes are key contributors in shaping the ultimate manifestations of decadal climate change (Diffenbaugh et al., 2005). Chapter 2 revealed certain similarities of extreme humid heat with extreme dry-bulb heat, most prominently in regions such as the eastern U.S. where the correlation of dry-bulb temperature and atmospheric moisture is high. There, a hot day is typically a humid one, and both variables reach their maximum values in mid-summer. In many other parts of the world, however, including locations where both temperature and moisture reach levels that far exceed those in the mid- latitudes, this correlation is much weaker. Correspondingly, the patterns of extreme humid heat are more complex, exhibiting major variations across regions and seasons. The contributions of moisture are in most cases the dominant force in determining where extreme humid heat occurs, and consequently, identifying its sources and transport mechanisms is crucial for predicting extreme humid heat on meteorological as well as climatological timescales. The relevant existing work in this field is highly localized or otherwise of narrow applicability, and broader conclusions rely, as I do here, on a certain amount of conjecture (Schär, 2016; Sherwood and Huber, 2010). In addition to further examining the role of the ocean, as mentioned above, evaporation (from natural water bodies or saturated soils), transpiration (from natural vegetation or crops), and moisture advection all must be thoroughly considered and partitioned to develop a more-complete picture of the key controlling mechanisms in a given region. The problem’s complexity lies in how these mechanisms may be contingent, co-dependent, time-varying, or interactive in many other ways.
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Projecting extreme heat-related mortality in Europe under climate change

Projecting extreme heat-related mortality in Europe under climate change

The main aim of this thesis is to develop techniques to project changes in extreme heat- related mortality in Europe under climate change. These techniques are illustrated through mortality projections from 2010 to 2099 using the output from perturbed physics ensem- ble of Hadley Centre regional climate model (RCM) HadRM3. The term ‘extreme heat- related mortality’ needs to be first defined. As will be described in Section 2.4, only a small proportion of the increased number of deaths on days with elevated temperatures is directly attributed to acute heat illnesses such as heat stroke (Kovats and Hajat, 2008). Therefore in this thesis, ‘heat-related mortality’ refers to the increased number of deaths from all causes related to increased air temperatures during the summer, as in AR4 of IPCC Working Group II (Section 8.4 in Confalonieri et al., 2007). As for the word ‘ex- treme’, which has various meanings in the climate science literature (Beniston et al., 2007; Stephenson, 2008), it is used in this thesis to refer to events with a low probability of oc- currence (i.e. rare events) with a significant impact on the society. A day with ‘extreme heat-related mortality’ is one with exceptionally large number of deaths caused by high air temperatures in the summer. For mortality projection purposes in this thesis, summer
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, orography, and oceanic heat transport on extreme climates

, orography, and oceanic heat transport on extreme climates

Does the orography matter in the initiation of extreme cli- mate? The LGM reconstruction of the orography (Peltier, 1994), including the highly elevated Laurentide Ice Sheet, reduces the global temperature by 3 ◦ C. The influence of changed orography predominates in the contribution to the Northern Hemispheric cooling, but it is of no importance to the tropics. Thus the altered orography is more impor- tant in regional sense, than in global. Jenkins and Frakes (1998) introduced a 2 km north-south mountain chain on the super continent in their Neoproterozoic model set up, and showed that the orogeny could not be considered as a factor for the global glaciation. But it can redistribute the humidity over sea-ice and thus, change the hydrological cycle (Don- nadieu et al., 2003). However, the climate system responses nonlinearly to linear change of the height of the ice-sheet (Romanova et al., 2005), which points to the existence of a threshold, over which a runaway albedo feedback over the American continent could be initiated. Further investigation of the sensitivity of the climate system toward enlargement of the Laurentide Ice Sheet could be of interest when searching for this threshold.
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Extreme heat and runoff extremes in the Swiss Alps

Extreme heat and runoff extremes in the Swiss Alps

We showed that regional hydrological responses to the 2003 summer heatwave can be related to the physical char- acteristics of the basins. More than 80% of the variabili- ty in the hydrological response of Swiss river basins to the 2003 heatwave can be explained by the average elevation and the degree of glacerization. During the 2003 heatwave, basins in the Swiss Central Plateau and basins with very low glacier portions (<1%) had less than 60% of the mean sum- mer runoff. Historical discharge minima were recorded in al- most all the lowland river basins whose long-term discharge records were too short to include the years 1947 and 1921. In alpine basins with up to 10% glacierization, icemelt provides a partial compensation of the reduced runoff generation in ice-free areas. The summer discharge is about 70–80% of the average. Basins with about 15% glacerization show the most interesting response to the 2003 heatwave. The addi- tional contribution of icemelt fully compensates for the limi- ted runoff generation in the remainder of the basin. Thus, the discharge during the summer of 2003 was very close to the historical annual and summer averages. At the same time, at sub-basin scales strong positive and strong negative anomalies in discharge were observed. Such an insight into mechanisms of hydrological extremes can only be attained through the application of distributed hydrological models. The disaggregation of the catchment response is very impor- tant in order to identify areas where such events can lead to environmental risks. Hydrological models might therefore be adopted for identifying the most sensitive regions where heatwaves may become a recurrent natural hazard with large social and economical impacts.
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Changes in extreme regional sea level under global warming

Changes in extreme regional sea level under global warming

Until 2100, global mean sea level is projected to rise up to roughly 1 m depending on the climate change scenario considered (Slangen et al., 2012, 2014). For example, under the SRES-A1B scenario, the global mean sea level is likely to rise between 0.42 and 0.80 m (compared to 1986–2005), with major contributions provided by thermal expansion of ocean water and the mass loss of the major ice sheets and glaciers (Church et al., 2013; Slangen et al., 2014). For the highest radiative forcing scenario (RCP8.5), projected global sea level rise is between 0.52 and 0.98 m in 2100 Church et al. (2013). Regional sea level changes projected for the North Atlantic show complex patterns that are partly caused by a weakening of the Atlantic Meridional Overturning Cir- culation (AMOC), by a shift in the path of the North Atlantic Current, and by changes in surface buoyancy fluxes (Lan- derer et al., 2007; Yin et al., 2010, 2009; Pardaens et al., 2011; Kienert and Rahmstorf, 2012; Bouttes et al., 2013). Thermosteric sea level evolves with a pattern that reflects the reduced heat transport to the North Atlantic due to changes in ocean currents (Yin et al., 2010; Pardaens et al., 2011). For example, DSL is rising near the North American continent because of a reduction in the AMOC causing a redistribution of ocean mass (Landerer et al., 2007; Yin et al., 2009, 2010; Bouttes et al., 2013).
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Climate, extreme heat, and electricity demand in California

Climate, extreme heat, and electricity demand in California

California is very dry during the summer and therefore this is not a significant factor for this region. In our analysis of changes in extreme heat we implicitly account for technology and population change through atmosphere-ocean general circulation model (AOGCMs) projections forced by the IPCC Special Report on Emission Scenarios (SRES) [Nakicenovic´ et al. 2000]. The SRES scenarios include a range of population increases and accompanying technological and societal changes. However, in the calculation of California’s regional energy demand we hold technology and population at today’s levels in order to quantify the range of possible outcomes as a perturbation about the historical demand. This perturbation approach has been used in previous impact assessment studies [e.g. IPCC 2001, USGCRP 2000]. It provides a constrained estimate of potential outcomes that can be extrapolated using a range of projected changes in population and technology applied to demand. In our discussion we explore the possibility of such extrapolated scenarios, although technological advancement is difficult, if not impossible, to project beyond about a 10 year timeline due to the large uncertainties pertaining to the rate of discovery, evaluation, and social adaptation of new technologies.
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Classification of Changes in Extreme Heat Over Southeastern Australia

Classification of Changes in Extreme Heat Over Southeastern Australia

exceeds the natural variability expected over a half century. Numerous maximum temperature records have been set and the extreme heat poses a major socioeconomic threat. This work examines changes in mean values of maximum daily temperatures for each summer month, in southeastern Australia. A 10-site dataset, for 1958-2013, was drawn and resampled to quantify temporal changes and uncertainty in decadal monthly maximum temperatures. Resampling methods documented the historical uniqueness of the maximum temperatures in recent decades. Results suggest strongly that, in recent decades, the maximum temperatures exceeding the upper quartile of the historical data is greater than expected by random chance. The findings confirm the regional nature of the warming. The increase in summer temperature is partly related to changes in atmospheric blocking.
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High-resolution regional modelling of changing extreme precipitation

High-resolution regional modelling of changing extreme precipitation

With a focus on the Black Sea and Mediterranean region, the July 2012 Krymsk precip- itation extreme was taken as a showcase example to study the sensitivity of an extreme precipitation event to SST increase. Convection-permitting simulations using SST states ranging from those representative to the early 1980s to those representative of 30 years beyond the event (assuming a continued warming trend) showed the crucial role of re- cent Black Sea warming in amplifying the Krymsk event. From the ensemble with the coldest to the ensemble with observed SSTs, sensible heating of the lower atmosphere by the warmer Black Sea led moisture availability to increase at close to that which would be expected based on the Clausius-Clapeyron relation, roughly 15%. Precipitation across the Krymsk region increased by over 300% though, between the same ensembles. This suggests limitations of the thermodynamical bounds (i.e. the CC relation) for predicting changes in convective precipitation extremes in coastal regions. Changes in dynamical factors, such as static stability, clearly also play an important role. The highly nonlinear response of the event’s intensity to SST increase - a sharp initial increase followed by a levelling-off - suggests that convective extremes in coastal regions may be governed by regional SST thresholds which favour more powerful systems. A warmer Black Sea acts as a store of heat, whose higher SSTs have the potential to increase instability and thus the probability of intense deep-convective events being triggered when suitable weather systems pass. SST increase is not a phenomenon unique to the BSM region; comparable regions undergoing SST increase could thus also be at risk of more intense convective extremes.
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Regional frequency analysis of extreme precipitation in Sicily (Italy)

Regional frequency analysis of extreme precipitation in Sicily (Italy)

https://doi.org/10.1002/joc.5400 Copyright: This is the peer reviewed version of the following article: Forestieri A, Lo Conti F, Blenkinsop S, Cannarozzo M, Fowler HJ, Noto LV. Regional frequency analysis of extreme precipitation for Sicily (Italy) . International Journal of Climatology 2018, which has been published in final form at

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The geographies of cyberspace

The geographies of cyberspace

Myself and Narushige Shiode are analysing the geographical patterns of ownership of Internet addresses in the UK at a very detailed scale. Preliminary results were presented at the Telecommunications and the City conference in Athens, Georgia (Dodge & Shiode 1998). Other notable research is being performed by Mitchell Moss and Anthony Townsend at the Taub Urban Research Center, New York University and Matt Zook, Department of City and Regional Planning, Berkeley (Zook 1998). Moss & Townsend examined the density of domain names for cities in the USA as a means of analysing the geographical patterns of Internet growth (Moss & Townsend 1997). They conclude that major “information-based” urban centres have been in the vanguard of Internet development, in particular “…New York city has the largest Internet presence of any city in the United States, and in all likelihood, the entire world.” (Moss & Townsend 1997:52).
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Can a regional climate model reproduce observed extreme temperatures?

Can a regional climate model reproduce observed extreme temperatures?

In order to adapt to a changing climate, policymakers need information about what to expect for the climate system. In particular, they need local information about changes in extreme weather. Such information typically comes from regional climate models (Rummukainen, 2010). A regional climate model is a downscaled global climate model, a mathematical model that describes, using partial differential equations, the temporal evolution of climate, oceans, atmosphere, ice, and land-use processes over a gridded spa- tial domain of interest. An important issue is how well the regional models reproduce observed extreme climate variables. There are several statistical problems associated with such comparisons. Models typically produce output on grids in space and time, while data are collected at various time scales at synoptic weather stations. Standard geostatistical methodology can be used to upscale station data to grid squares (Berro- cal et al., 2012), but there are no geostatistical tools that can be directly used to upscale station extremes to grid square extremes.
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Joining the Dots  Universities’ roles in integrating local, regional, national and international geographies

Joining the Dots Universities’ roles in integrating local, regional, national and international geographies

Recent developments in the UK for University and anchor strategies have been informed by the US experience (CLES 2015b). Preston City Council’s work with CLES (2015a) has engaged a range of anchor institutions including local Colleges and Universities to introduce measures (such as increasing local procurement spend, co-production with community organisations, engagement to build capacity with local business networks) to maximise impact and community benefit for the locality (CLES 2015a). The long term ambition is to foster ‘a good local economy’, enhance resilience and deliver greater prosperity with both economic and social progress (CLES 2015a). Universities undertake a major role within local, national and regional geographies. Anchor Institutions (including Universities, Local Authorities, Local Enterprise Partnerships and Combined Authorities) and their decision-makers provide influential ‘regional leadership’ and ‘legitimacy’ for enhanced regional effectiveness and for joined up actions for strategy, delivery and bridging the divide between these agendas (North, Syrett and Etherington, 2007). As such, understanding how to maximise the contribution of Universities and other Anchor Institutions for sustainable development (economic, social and environmental development) in City Regions through integrated joined up anchor engagement strategies could make an enhanced contribution to the shaping of policy and practice for city-regional development.
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Planner’s primer on extreme heat events and hazard mitigation planning

Planner’s primer on extreme heat events and hazard mitigation planning

The Extreme Heat Hazard Assessment opens by defining extreme heat events as a period of “prolonged temperatures…10° or more above the average high temperature for the region” (Baltimore Office of Sustainability, 2013, p. 84). This definition is not placed into context through the inclusion of average high temperatures for Baltimore nor is the definition source provided. The authors move the discussion to the history of extreme heat events in Baltimore. The authors review the annual average number of extreme heat events, the projected number of extreme heat events given the amplifying effects of climate change, and the lengthiest extreme heat events to impact Baltimore. The authors also developed a time series graph depicting individual extreme heat events as a value of the number of degrees above 97°F for the events average high temperature (Baltimore Office of Sustainability, 2013, p. 87). No reference for the source of information is provided. The 2013 multi-hazard mitigation plan builds upon the knowledge established in the 2006 All-Hazards Plan on the urban heat island effect by including imagery depicting Baltimore’s developed land and land surface temperatures (Baltimore Office of Sustainability, 2013, p. 85). The Extreme Heat Hazard Assessment concludes by identifying the health risks (heat stress, heat exhaustion, and heat stroke) associated with extreme heat events and populations at greater risk of being affected (the elderly, young children, and people with respiratory difficulties) (Baltimore Office of Sustainability, 2013, p. 86).
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Sophisticated Geographies

Sophisticated Geographies

Nowadays, the sophist’s sensitivity to difference would not necessarily result in their project being so negatively construed. Indeed, Jarratt’s own positively inflected reclamation of the sophists turns upon the fact that they were “skeptical about a divine source of knowledge or value” and instead sensitive to knowledge as formed “in historically and geographically specific contexts” (1991, xx). One way of thinking about this is to say that the ancient sophists were both geographers and philosophers. Although it is also to admit that it was their geography – their emphasis on the situatedness of knowledge – that was their undoing in relation to later developments in philosophical thought. This arrangement stands in contrast to what we see in many contemporary geographies, in which it is their claim to being philosophical that can give rise to a scepticism among some readers. Indeed, when ‘big theory’ touches empirically grounded geographies indifferently or when ‘big theory’ seems to preclude doing empirically grounded geographies altogether, then the claim against such geographies may
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Arizona Department of Health Services Extreme Heat Incident Annex

Arizona Department of Health Services Extreme Heat Incident Annex

This plan will describe how ADHS will utilize the Public Health Incident Management System (PHIMS) to coordinate and manage an extreme heat incident affecting or having the potential to affect the public health system of the State of Arizona. This annex will describe the concepts of operations, roles and responsibilities of ADHS and its partners, and outline methods used to share essential elements of information (EEI) between these partners and other stakeholders.

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Research Article Mapping Urban Heat Vulnerability of Extreme Heat in Hangzhou via Comparing Two Approaches

Research Article Mapping Urban Heat Vulnerability of Extreme Heat in Hangzhou via Comparing Two Approaches

Copyright © 2020 Xue Liu et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Extreme heat is the leading cause of heat-related mortality around the world. Extracting heat vulnerability information from the urban complexity system is crucial for urban health studies. Using heat vulnerability index (HVI) is the most common approach for urban planners to locate the places with high vulnerability for intervention and protection. Previous studies have demonstrated that HVI can play a vital role in determining which areas are at risk of heat-related deaths. Both equal weight approach (EWA) and principal component analysis (PCA) are the conventional methods to aggregate indicators to HVI. However, seldom studies have compared the differences between these two approaches in estimating HVI. In this paper, we evaluated the HVIs in Hangzhou in 2013, employing EWA and PCA, and assessed the accuracies of these two HVIs by using heat-related deaths. Our results show that both HVI maps showed that areas with high vulnerability are located in the central area while those with low vulnerability are located in the suburban area. The comparison between HVI EWA and HVI PCA shows significantly different spatial distributions,
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Indoor-outdoor environmental coupling and exposure risk to extreme heat and poor air quality during heat waves

Indoor-outdoor environmental coupling and exposure risk to extreme heat and poor air quality during heat waves

As suggested above, building management practices and occupant behavior both play important roles in mediating the connections between outdoor and indoor atmospheric environments and occupant exposure to extreme heat and poor air quality. The type, magnitude, and timing of mechanical and natural ventilation affect the exchange of indoor and outdoor air in complex ways. While filters are generally intended to remove particulate matter from the air, filters heavily loaded with organic compounds may actually provide an additional ozone scrubbing effect associated with deposition and surface reactions (Hyttinen et al., 2005). Thus, replacing filters during the high ozone season may actually have an adverse effect on indoor concentrations of ozone. Assisted living facilities have a number of other management practices that can affect indoor air quality. This ranges from the routine use of high volatile organic compound (VOC) emitting cleaning supplies to periodic maintenance such as painting and replacement of carpets. It is not uncommon, for example, for an assisted living facility to repaint a recently vacated apartment in preparation for a new occupant. Such apartments are typically rented out to new residents within a fairly short time, after the paint has cured substantially, but is still a potentially high emitter of VOCs that react with ozone to produce potentially harmful byproducts. Also, the relative timing of HVAC operations and maintenance and cleaning may play an important role in how indoor and outdoor air interact chemically.
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Avian thermoregulation in the heat: efficient evaporative cooling allows for extreme heat tolerance in four southern hemisphere columbids

Avian thermoregulation in the heat: efficient evaporative cooling allows for extreme heat tolerance in four southern hemisphere columbids

largely restricted to two orders, Columbiformes and Passeriformes (Tieleman and Williams, 2002; Wolf and Walsberg, 1996), and patterns of EWL partitioning in other orders remain less clear. One reason behind the paucity of data for many orders is that measuring REWL and CEWL is more technically challenging than measuring total evaporation, and requires either a partitioned chamber in which REWL and CEWL are measured in separate compartments (e.g. Hoffman and Walsberg, 1999; Lasiewski et al., 1971; Wolf and Walsberg, 1996) or a mask system (e.g. Tieleman and Williams, 2002). Both these approaches require that birds be habituated to the experimental setup, and that chambers and/or masks be custom- built for particular study species. However, the pronounced differences in heat tolerance and evaporative cooling capacity between the only two orders that are relatively well studied in this regard highlight the need for quantitative data on the contributions of REWL and CEWL to total evaporation in many more avian taxa. Such data are a prerequisite for fully understanding phylogenetic variation among birds in heat tolerance and evaporative cooling capacity.
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ISO Extreme Weather Indices: Heat Data Product Specification. Revision: A

ISO Extreme Weather Indices: Heat Data Product Specification. Revision: A

Environment and Climate Change Canada generates the extreme weather indices on a global scale. Agriculture and Agri-food Canada accesses the daily datasets in netCDFformat. Each dataset is converted to a TIFF file, projected to the Web Mercator projection (EPSG 3857), and clipped to an extent encompassing Canada and the continental United States, defined by a rectangle with latitude boundaries of 24°N and 90°N and longitude boundaries of 180°W and 50°W.

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Turning up the heat on admissions: A study of the impacts of extreme heat events on Tasmanian hospital admissions 2003-2010

Turning up the heat on admissions: A study of the impacts of extreme heat events on Tasmanian hospital admissions 2003-2010

References 1. Tong S, Wang, XY, Barnet AG. Assessment of heat-related health impacts in Brisbane, Australia: comparison of different heatwave definitions. PLoS One 2010;5(8):e12155. 2. McGeehin MA, Mirabelli M. The Potential Impacts of Climate Variability and Change on temperature- Related Morbidity and Mortality in the United States. Environmental health Perspectives 2001; 109(Suppl 2):185-9.

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