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Climate-driven reproductive decline in Southern right whales
Charlton, Claire; Germishuizen, Matthew; O'Shannessy, Bridgette; McCauley, Robert; Vermeulen, Els; Seyboth, Elisa; Brownell, Robert L.; Burnell, Stephen (Nature Research, 2026-02)
Reproductive success and abundance trends in migratory baleen whales are linked to body condition and foraging success, making them vulnerable to changes in prey availability which is influenced by climate variation. Southern right whales (Eubalaena australis), a sentinel species for climate change, offer critical insight into Southern Ocean health. Using over three decades (1991–2024) of photo-identification data collected in southwest Australia, we document a significant decline in reproductive output driving a slowed rate of population increase in the last decade. Cross-correlation and principal component analyses reveal that prolonged calving intervals coincide with declining Antarctic Sea ice concentration, persistent positive Antarctic Oscillation, and increases in surface chlorophyll-a, signalling broader ecosystem shifts. These findings add to global evidence of the sensitivity of southern right whales to climate variability in their offshore foraging grounds. This reproductive decline represents a threshold warning for the species and highlights the need for coordinated conservation efforts in the Southern Ocean, in the face of anthropogenic climate change.
Climate-adaptive energy strategies for sustainable greenhouse systems : a Köppen-based systematic review
Dong, Yun; Ye, Xianming; Lin, Dong; Zhang, Lijun; Xia, Xiaohua (Elsevier, 2026-03)
Greenhouses are essential for enhancing crop yields and enabling year-round production, but their high energy intensity and climate-sensitive demand challenge sustainability. To address the lack of climate-stratified evidence, we conduct a systematic review of climate-adaptive energy approaches for greenhouse systems structured by the Köppen climate classification (KCC). We searched the Web of Science (2019–2024) using Topic “greenhouse”, limiting to articles and refining by the “Citation Topic Micro: Greenhouse” filter; 276 records were identified and 268 articles were retained after title and abstract screening. The evidence is organized into four domains: (1) microclimate modeling and decision-support tools, (2) passive design and device-assisted enhancements, (3) active operational optimization, and (4) renewable energy integration. Results reveal climate-specific patterns: cold and arid regions most consistently benefit from insulation, thermal screens, phase-change storage, and solar–thermal-assisted heating; temperate and tropical climates increasingly adopt advanced control, including model predictive control and data-driven/learning-based controllers, to coordinate multi-variable microclimate-energy trade-offs. Renewable integration is expanding across zones, yet harmonized techno-economic and life-cycle assessments remain limited. This KCC-based synthesis supports region-specific design and operation decisions and highlights priorities for future research and deployment. HIGHLIGHTS • Climate-based framework for greenhouse energy. • Köppen classification applied to greenhouse sustainability. • Passive, active, and renewable approaches systematically reviewed. • Climate-specific energy patterns identified across global zones. • Guidance for sustainable, low-carbon greenhouse production.
Mapping customer value propositions for retirement housing facilities in South Africa
Berndt, Adele; Tesnear, Sumari (Adonis & Abbey, 2026-03)
The South African retirement housing market is expanding to meet increasing demand from retirees. Facility managers develop customer value propositions to inform retirees of the expected value. Given the growth in this sector and the lack of academic research into customer value proposition design, this study explores the components of customer value propositions in South African retirement housing facilities using customer value proposition mapping. Using an interpretivist approach, data (118 web posts) were collected from a senior citizens’ retirement housing website and analysed through content analysis. The key findings identified gain creators (such as medical and leisure services), pain relievers (such as security services), and relevant products (such as meal offerings) included in the propositions, with a primary focus on gain creators. This study underscores the necessity of aligning facility management with the nuanced requirements of retirees, providing a strategic framework for decision-making within a traditionally under-researched sector.
Climate risks and predictability of the conditional distributions of rare earth stock returns and volatility
Polat, Onur; Gupta, Rangan; Bouri, Elie; Brahim, Mariem (Springer, 2026-02)
Using a nonparametric causality-in-quantiles test, we examine the predictability of rare earth stock returns and volatility based on physical and transition climate risks over the period 2nd January 2008 to 31st January 2025. Our results indicate that, although the linear Granger causality test fails to show any evidence of predictability due to model misspecifications arising from nonlinearity and structural breaks, the nonparametric causality-in-quantiles test shows significant predictability over the entire conditional distribution of rare earth stock returns and volatility. The evidence of predictability is robust to alternative choices of rare earth stock indexes, measures of climate risk, conditional estimates of volatility, and multiple macroeconomic and financial control variables. Further analyses involving the signs of the causal impact and a rolling-window estimation reveal that returns are negatively impacted over the range of lower conditional quantiles till the median, corresponding to weak global conditions; volatility, however, is increased over its entire conditional distribution. The implications of our findings are discussed.
Climate change in South African rivers : a case study on the Olifants River in the Kruger National Park
Adlam, Amanda Laura; Chimimba, Christian Timothy; Retief, D.C. Hugo; Woodborne, Stephan M. (Academy of Science of South Africa, 2026-03)
Freshwater systems are among the most endangered ecosystems, with anthropogenic climate change causing detrimental ecological and economic impacts. Due to climate change, increased air temperatures will translate into the warming of rivers, and at the same time will alter flow regimes and increase evaporation and stochastic events. In this study, we used validated statistical water temperature models that predict average water temperatures (WTavg) from air temperature to project monthly and daily WTavg from 2025 to 2100 CE in the heavily polluted and over-abstracted Olifants River, Kruger National Park, Limpopo Province, South Africa, under the ‘business as usual’ Representative Concentration Pathway 8.5 scenario. The results from 16 General Circulation Models showed that monthly WTavg is likely to increase by 3.6 °C and showed summer months reaching up to 34–35 °C by 2100 CE. The daily results showed a similar increase of 3.7 °C by 2100 CE, with some extreme days reaching 42–44 °C. These results support similar research conducted within the Olifants catchment of the Limpopo Basin and add to the limited knowledge of freshwater climate change, especially in Africa. Climate change will ultimately alter the thermal and physical landscape of the Olifants River and this forecast highlights the need for further research on the potential detrimental consequences on freshwater biota, including possible local extinctions. SIGNIFICANCE • Increasing air temperature due to anthropogenic climate change will cause water temperatures to rise. • Statistical models can be used to predict future water temperatures from air temperature. • The projections show an increase in monthly average water temperature (WTavg) of 3.6 °C and an increase in daily WTavg of 3.7 °C by the end of the 21st century. • This drastic rise in water temperatures will ultimately have negative effects on freshwater biota.