scholarly journals Disentangling the impacts of heat wave magnitude, duration and timing on the structure and diversity of sessile marine assemblages

PeerJ ◽  
2015 ◽  
Vol 3 ◽  
pp. e863 ◽  
Author(s):  
Dan A. Smale ◽  
Anna L.E. Yunnie ◽  
Thomas Vance ◽  
Stephen Widdicombe

Extreme climatic events, including heat waves (HWs) and severe storms, influence the structure of marine and terrestrial ecosystems. Despite growing consensus that anthropogenic climate change will increase the frequency, duration and magnitude of extreme events, current understanding of their impact on communities and ecosystems is limited. Here, we used sessile invertebrates on settlement panels as model assemblages to examine the influence of HW magnitude, duration and timing on marine biodiversity patterns. Settlement panels were deployed in a marina in southwest UK for ≥5 weeks, to allow sufficient time for colonisation and development of sessile fauna, before being subjected to simulated HWs in a mesocosm facility. Replicate panel assemblages were held at ambient sea temperature (∼17 °C), or +3 °C or +5 °C for a period of 1 or 2 weeks, before being returned to the marina for a recovery phase of 2–3 weeks. The 10-week experiment was repeated 3 times, staggered throughout summer, to examine the influence of HW timing on community impacts. Contrary to our expectations, the warming events had no clear, consistent impacts on the abundance of species or the structure of sessile assemblages. With the exception of 1 high-magnitude long-duration HW event, warming did not alter not assemblage structure, favour non-native species, nor lead to changes in richness, abundance or biomass of sessile faunal assemblages. The observed lack of effect may have been caused by a combination of (1) the use of relatively low magnitude, realistic heat wave treatments compared to previous studies (2), the greater resilience of mature adult sessile fauna compared to recruits and juveniles, and (3) the high thermal tolerance of the model organisms (i.e., temperate fouling species, principally bryozoans and ascidians). Our study demonstrates the importance of using realistic treatments when manipulating climate change variables, and also suggests that biogeographical context may influence community-level responses to short-term warming events, which are predicted to increase in severity in the future.

2019 ◽  
Vol 76 (Suppl 1) ◽  
pp. A73.2-A73
Author(s):  
Matthias Otto ◽  
Tord Kjellstrom ◽  
Bruno Lemke

Exposure to extreme heat negatively affects occupational health. Heat stress indices like Wet Bulb Globe Temperature (WBGT) combine temperature and humidity and allow quantifying the climatic impact on human physiology and clinical health. Multi-day periods of high heat stress (aka. heat waves) affect occupational health and productivity independently from the absolute temperature levels; e.g. well-documented heat-waves in Europe caused disruption, hospitalisations and deaths (2003 French heat wave: more than 1000 extra deaths, 15–65 years, mainly men) even though the temperatures were within the normal range of hotter countries.Climate change is likely to increase frequency and severity of periods of high heat stress. However, current global grid-cell based climate models are not designed to predict heat waves, neither in terms of severity or frequency.By analysing 37 years of historic daily heat index data from almost 5000 global weather stations and comparing them to widely used grid-cell based climate model outputs over the same period, our research explores methods to assess the frequency and intensity of heat waves as well as the associated occupational health effects at any location around the world in the future.Weather station temperature extreme values (WBGT) for the 3 hottest days in 30 years exceed the mean WBGT of the hottest month calculated from climate models in the same grid-cell by about 2 degrees in the tropics but by 10 degrees at higher latitudes in temperate climate regions.Our model based on the relationship between actual recorded periods of elevated heat-stress and grid-cell based climate projections, in combination with population and employment projections, can quantify national and regional productivity loss and health effects with greater certainty than is currently the case.


2020 ◽  
Author(s):  
Paul Hamer ◽  
Heidelinde Trimmel ◽  
Philipp Weihs ◽  
Stéphanie Faroux ◽  
Herbert Formayer ◽  
...  

<p>Climate change threatens to exacerbate existing problems in urban areas arising from the urban heat island. Furthermore, expansion of urban areas and rising urban populations will increase the numbers of people exposed to hazards in these vulnerable areas. We therefore urgently need study of these environments and in-depth assessment of potential climate adaptation measures.</p><p>We present a study of heat wave impacts across the urban landscape of Vienna for different future development pathways and for both present and future climatic conditions. We have created two different urban development scenarios that estimate potential urban sprawl and optimized development concerning future building construction in Vienna and have built a digital representation of each within the Town Energy Balance (TEB) urban surface model. In addition, we select two heat waves of similar frequency of return representative for present and future conditions (following the RCP8.5 scenario) of the mid 21<sup>st</sup> century and use the Weather Research and Forecasting Model (WRF) to simulate both heat wave events. We then couple the two representations urban Vienna in TEB with the WRF heat wave simulations to estimate air temperature, surface temperatures and human thermal comfort during the heat waves. We then identify and apply a set of adaptation measures within TEB to try to identify potential solutions to the problems associated with the urban heat island.</p><p>Global and regional climate change under the RCP8.5 scenario causes the future heat wave to be more severe showing an increase of daily maximum air temperature in Vienna by 7 K; the daily minimum air temperature will increase by 2-4 K. We find that changes caused by urban growth or densification mainly affect air temperature and human thermal comfort local to where new urbanisation takes place and does not occur significantly in the existing central districts.</p><p>Exploring adaptation solutions, we find that a combination of near zero-energy standards and increasing albedo of building materials on the city scale accomplishes a maximum reduction of urban canyon temperature of 0.9 K for the minima and 0.2 K for the maxima. Local scale changes of different adaption measures show that insulation of buildings alone increases the maximum wall surface temperatures by more than 10 K or the maximum mean radiant temperature (MRT) in the canyon by 5 K.  Therefore, additional adaptation to reduce MRT within the urban canyons like tree shade are needed to complement the proposed measures.</p><p>This study concludes that the rising air temperatures expected by climate change puts an unprecedented heat burden on Viennese inhabitants, which cannot easily be reduced by measures concerning buildings within the city itself. Additionally, measures such as planting trees to provide shade, regional water sensitive planning and global reduction of greenhouse gas emissions in order to reduce temperature extremes are required.</p><p>We are now actively seeking to apply this set of tools to a wider set of cases in order to try to find effective solutions to projected warming resulting from climate change in urban areas.</p>


Author(s):  
S. Snizhko ◽  
O. Shevchenko ◽  
H. Svintsitska

On the basis of 10 selected stations of the meteorological network heat wave episodes for Сentral regions of Ukraine in the summer months June to August in 1961–2015 have been identified. Duration, intensity and temporal variability of heat wave cases are analyzed. It is proved that the heat wave observed at the end of July – the first part of August 2010 was the longest and the most intense nearly for all stations of the Central regions of Ukraine during the research period. Keywords: heat wave, heat wave duration, heat wave intensity, climate change.


2020 ◽  
Vol 10 (3) ◽  
pp. 1149 ◽  
Author(s):  
Alfredo Rocha ◽  
Susana C. Pereira ◽  
Carolina Viceto ◽  
Rui Silva ◽  
Jorge Neto ◽  
...  

Heat waves are large-scale atmospheric phenomena that may cause heat stress in ecosystems and socio-economic activities. In cities, morbidity and mortality may increase during a heat wave, overloading health and emergency services. In the face of climate change and associated warming, cities need to adapt and mitigate the effects of heat waves. This study suggests a new method to evaluate heat waves’ impacts on cities by considering some aspects of heat waves that are not usually considered in other similar studies. The method devises heat wave quantities that are easy to calculate; it is relevant to assessing their impacts and permits the development of adaptation measures. This study applies the suggested method to quantify various aspects of heat waves in Lisbon for future climate projections considering future mid-term (2046–2065) and long-term (2081–2100) climates under the RCP8.5 greenhouse emission scenario. This is achieved through the analysis of various regional climate simulations performed with the WRF model and an ensemble of EURO-CORDEX models. This allows an estimation of uncertainty and confidence of the projections. To evaluate the climate change properties of heat waves, statistics for future climates are compared to those for a reference recent climate. Simulated temperatures are first bias corrected to minimize the model systematic errors relative to observations. The temperature for mid and long-term futures is expected to increase relative to the present by 1.6 °C and 3.6 °C, respectively, with late summer months registering the highest increases. The number of heat wave days per year will increase on average from 10, in the present climate, to 38 and 63 in mid and long-term climates, respectively. Heat wave duration, intensity, average maximum temperature, and accumulated temperature during a heat wave will also increase. Heat waves account for an annual average of accumulated temperature of 358 °C·day in the present climate, while in the mid and long-term, future climates account for 1270 °C·day and 2078 °C·day, respectively. The largest increases are expected to occur from July to October. Extreme intensity and long-duration heat waves with an average maximum temperature of more than 40 °C are expected to occur in the future climates.


2018 ◽  
Vol 10 (4) ◽  
pp. 731-746 ◽  
Author(s):  
Matthew J. Cutler ◽  
Jennifer R. Marlon ◽  
Peter D. Howe ◽  
Anthony Leiserowitz

Abstract Vulnerability and resilience to extreme weather hazards are a function of diverse physical, social, and psychological factors. Previous research has focused on individual factors that influence public perceptions of hazards, such as politics, ideology, and cultural worldviews, as well as on socioeconomic and demographic factors that affect geographically based vulnerability, environmental justice, and community resilience. Few studies have investigated individual socioeconomic and racial/ethnic differences in public risk perceptions of the health hazards associated with extreme heat events, which are now increasing due to climate change. This study uses multilevel statistical modeling to investigate individual- and geographic-level (e.g., census tract level and regional) social, economic, and biophysical influences on public perceptions of the adverse health impacts associated with heat waves. Political orientation and climate change beliefs are the strongest predictors of heat wave health risk perceptions; household income also has a relatively strong and consistent effect. Contextual socioeconomic vulnerability, measured with a social vulnerability index at the census tract level, also significantly affects heat wave risk perceptions. The strong influence of political orientation and climate beliefs on perceptions of adverse health impacts from heat waves suggests that ideological predispositions can increase vulnerability to climate change.


Climate ◽  
2014 ◽  
Vol 3 (1) ◽  
pp. 100-117 ◽  
Author(s):  
Stefan Zacharias ◽  
Christina Koppe ◽  
Hans-Guido Mücke

2021 ◽  
Vol 21 (1) ◽  
pp. 301-310
Author(s):  
Jiyu Seo ◽  
Jeongeun Won ◽  
Jeonghyeon Choi ◽  
Okjeong Lee ◽  
Sangdan Kim

Due to global warming, there is an increasing concern regarding persistent and severe heat waves. The maximum daily surface air temperature observations show strong non-stationary features, and the increased intensity and persistence of heat wave events have been observed in many regions. The heat wave persistence day frequency (HPF) curve, which correlates the intensity of a heat wave persistence event for days with return periods, can be a useful tool to analyze the frequency of heat wave events. In this study, non-stationary HPF curves are developed to explain the trend in the increase of the surface air temperature due to climate change, and their uncertainty is analyzed. The non-stationary HPF model can be used in climate change adaptation management such as public health, public safety, and energy management.


2016 ◽  
Vol 13 (21) ◽  
pp. 5947-5964 ◽  
Author(s):  
Eva van Gorsel ◽  
Sebastian Wolf ◽  
James Cleverly ◽  
Peter Isaac ◽  
Vanessa Haverd ◽  
...  

Abstract. As a result of climate change warmer temperatures are projected through the 21st century and are already increasing above modelled predictions. Apart from increases in the mean, warm/hot temperature extremes are expected to become more prevalent in the future, along with an increase in the frequency of droughts. It is crucial to better understand the response of terrestrial ecosystems to such temperature extremes for predicting land-surface feedbacks in a changing climate. While land-surface feedbacks in drought conditions and during heat waves have been reported from Europe and the US, direct observations of the impact of such extremes on the carbon and water cycles in Australia have been lacking. During the 2012/2013 summer, Australia experienced a record-breaking heat wave with an exceptional spatial extent that lasted for several weeks. In this study we synthesised eddy-covariance measurements from seven woodlands and one forest site across three biogeographic regions in southern Australia. These observations were combined with model results from BIOS2 (Haverd et al., 2013a, b) to investigate the effect of the summer heat wave on the carbon and water exchange of terrestrial ecosystems which are known for their resilience toward hot and dry conditions. We found that water-limited woodland and energy-limited forest ecosystems responded differently to the heat wave. During the most intense part of the heat wave, the woodlands experienced decreased latent heat flux (23 % of background value), increased Bowen ratio (154 %) and reduced carbon uptake (60 %). At the same time the forest ecosystem showed increased latent heat flux (151 %), reduced Bowen ratio (19 %) and increased carbon uptake (112 %). Higher temperatures caused increased ecosystem respiration at all sites (up to 139 %). During daytime all ecosystems remained carbon sinks, but carbon uptake was reduced in magnitude. The number of hours during which the ecosystem acted as a carbon sink was also reduced, which switched the woodlands into a carbon source on a daily average. Precipitation occurred after the first, most intense part of the heat wave, and the subsequent cooler temperatures in the temperate woodlands led to recovery of the carbon sink, decreased the Bowen ratio (65 %) and hence increased evaporative cooling. Gross primary productivity in the woodlands recovered quickly with precipitation and cooler temperatures but respiration remained high. While the forest proved relatively resilient to this short-term heat extreme the response of the woodlands is the first direct evidence that the carbon sinks of large areas of Australia may not be sustainable in a future climate with an increased number, intensity and duration of heat waves.


2016 ◽  
Vol 9 ◽  
pp. ASWR.S32778 ◽  
Author(s):  
Polioptro F. Martínez Austria ◽  
Erick R. Bandala

Maximum temperature trends and the corresponding heat wave thresholds in the northwestern city of Mexicali, Mexico, were analyzed using historical data from the site. We found that there seems to be an upward trend in temperature in the past decades, along with an increased number of days reaching maximum temperatures considered as heat waves. Despite the difficulty of establishing heat wave parameters, the trends of the analyzed field data clearly show their presence, mainly during July and August. This trend is also supported by the analysis of the number of admissions and casualties registered in hospitals in the city of Mexicali. This work is a warning on the frequency and duration of a very important climate change-related effect capable of jeopardizing the health of the population in the region and requiring more attention by decision makers and stakeholders. It also helps to document observed climate trends, as requested by the Intergovernmental Panel for Climate Change.


2019 ◽  
Vol 29 (Supplement_4) ◽  
Author(s):  
P Van Den Hazel

Abstract Background There is a growing amount of climate change and health data available in open sources. Inhabitants value their neighbourhood mostly by perception. Local authorities make spatial planning discussions based on environmental data. In the case of heat waves more climate adaptation measures are taken by authorities. However, there is a gap in knowledge on the need for adaptation of our environment and the perception of a growing proportion of the population on the need for adaptation. Furthermore, there is little focus on the mental problems related to climate change. The example of heat wave adaptation has been studied. Methods Heat wave plans across Europe have been analysed on participatory processes by the population or by broader group of stakeholders in the health care sector. The existing plans of 20 countries were collected. Interviews with key-persons involved in the implementation of these plans were used. The perception of the population on the measures, the mentioning of individual or group resilience and for mental disturbances during or in the aftermath of a heat wave were studied. Results The results show limited attention for the participatory process in heat wave plans. There is no attention for mental problems. Resilience is only addressed the way that simple message is conveyed through the media. There is limited focus on vulnerable groups in society. Conclusions It would help if the local authorities would make decisions in adaptation of their spatial planning to include the perception of the population and to focus on some vulnerable groups in society. The extension of caring about vulnerable groups beyond the period of heat waves is needed.


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