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Peatlands store disproportionally large amounts of carbon per unit area, a function that is dependent on maintaining high and stable water tables. Climate change is likely to negatively impact carbon storage in peatlands, in part due to increases in vapour pressure deficit (VPD) driving higher evaporation (E) rates. However, the response of E to increasing VPD depends on the dominant vegetation type within peatlands. In this study, we used multiple years of eddy covariance (EC) measurements to compare E regimes at two peatlands with contrasting vegetation types – Kopuatai bog in Aotearoa / New Zealand, dominated by the vascular wire rush Empodisma robustum, and Mer Bleue bog in Canada, a "typical" shrub- and moss-dominated Northern Hemisphere peatland. We examined seasonal variability in E and equilibrium E (Eeq), energy balance partitioning, and the response of E , evaporative fraction (EF), and canopy conductance (gc) to VPD. Mean annual E was 45 % lower than mean annual Eeq at Kopuatai but only 16 % lower at Mer Bleue, demonstrating much greater limitations on E at Kopuatai. In addition, the mean midday (10:00–14:30 local standard time) dry-canopy Bowen ratio (β) at Kopuatai was 2.0 compared to 0.8 at Mer Bleue; therefore, the sensible heat flux (H) dominated over the latent heat flux (LE) at Kopuatai and vice versa at Mer Bleue. The responses of E , EF, and gc to increasing VPD at Kopuatai demonstrated stronger limitations on evaporative water loss for VPD > 0.7 kPa compared to Mer Bleue. The observed limitations at Kopuatai were attributed to strong stomatal control by E. robustum due to the rapid decrease in gc with increasing VPD; however, surface E could also be limited by its dense standing litter. At Mer Bleue, however, E was only weakly limited at VPD > 2 kPa, likely due to weak stomatal control over transpiration by the sparse shrub canopy and relatively large surface E from Sphagnum carpets. As such, the results of this study suggest that E. robustum drives a greater "hydrological resistance" to increasing VPD than the vegetation at Mer Bleue, leading to greater water retention at Kopuatai. This may enable greater resilience of the carbon sink function at Kopuatai to climatic warming and drying than at Mer Bleue. [ABSTRACT FROM AUTHOR]

This study explores sense-making about climate engineering among lay focus group participants in Japan, New Zealand, the USA and Sweden. In total, 23 qualitative focus group interviews of 136 participants were conducted. The analyses considered sense-making strategies and heuristics among the focus group participants and identified commonalities and variations in the data, exploring participants' initial and spontaneous reactions to climate engineering and to several recurrent arguments that feature in scientific and public debate (e.g. climate emergency). We found that, despite this study's wide geographical scope, heterogeneous focus group compositions, and the use of different moderators, common themes emerged. Participants made sense of climate engineering in similar ways, for example, through context-dependent analogies and metaphorical descriptions. With few exceptions, participants largely expressed negative views of large-scale deliberate intervention in climate systems as a means to address anthropogenic global warming. [ABSTRACT FROM AUTHOR]

Glacial landscapes preserve records of past climate change. Investigating the glacier–climate system over the Late Quaternary provides information about past climate change and context for present‐day glacier response to climate warming. Using 28 beryllium‐10 (10Be) surface exposure dates and snowline reconstructions, we present glacier fluctuations and climate changes for the Antarctic Cold Reversal in the Ahuriri River catchment, Southern Alps of New Zealand (44°7′50″S, 169°38′29″E). Prominent terminal and lateral moraine features from the upper right tributary of the Ahuriri River valley have exposure ages of 14.5 ± 0.3, 13.6 ± 0.3 and 12.6 ± 0.2 ka, suggesting retreat of the glacier during the Antarctic Cold Reversal. Maximum elevation of lateral moraines (MELM) and accumulation area ratio (AAR) suggest snowline elevations at these ages were ≤700, ≤630 and ~360 m lower than today, respectively. This equates to air temperatures ≤3.9, ≤3.5 and 2.3 ± 0.7 °C lower than today (1981–2010), assuming no changes in past precipitation. Ice‐sculpted bedrock surfaces bound by a lateral moraine at nearby Canyon Creek have an age of 13.1 ± 0.3 ka, indicating the moraine correlates with those in the Ahuriri upper right tributary. MELM and AAR reconstructions from the Canyon Creek suggest that snowline elevations at 14.5–13.6 ka were ≤500 or ~380 m lower than today, corresponding to air temperatures ≤2.8 or 2.4 ± 0.7 °C lower than the present‐day (1981–2010). Our results provide insight into the structure of the Antarctic Cold Reversal in the Southern Alps, showing that the largest glacier advance occurred at the start of this interval at c. 14.5 ± 0.3 ka and was followed by gradual retreat. We hypothesize that the early cooling and glacier readvance in New Zealand at the onset of the Antarctic Cold Reversal were triggered by a latitudinal shift of the Southern Hemisphere westerly wind belt. [ABSTRACT FROM AUTHOR]

Seagrass ecosystem provides valuable ecosystem services and is significant blue carbon sink. This resource, however, has been degraded across the globe with a loss rate of 7% year−1 to the end of twentieth century. The loss of seagrass meadows might lead to an unexpected emission of CO2 into the atmosphere, aggravating global warming and resulting in potential damages to regional ecology and economies. Accurate mapping of meadows extent in different coverages from remotely sensed data, therefore is in high demand as the first step in the strategy of monitoring, report, verification (MRV) that underpins large scale conservation of global seagrass. Despite the higher accuracy of seagrass mapping in recent years, several challenges still persist, particularly when dealing with degraded, sparse seagrass meadows. In this research, we propose a novel and high accuracy approach for mapping dense and sparse meadows of the small size Zostera muelleri seagrass, using high spatial resolution imagery (PlanetScope) at 3 m spatial resolution, and advanced machine learning (ML) models for a ten-fold cross-validation superpixel-based classification in Tauranga Harbour, New Zealand. We archive high mapping accuracy (overall accuracy = 0.913, Kappa coefficient (κ) = 0.786, Matthews correlation coefficient (MCC) = 0.796 and F1 = 0.908) using the LightGBM model from a set of superpixel image coupled with the Bayesian optimization for hyper-parameter tuning. Our proposed approach is solid and reliable with evidences of improving κ (10%) and MCC (11%) when compared with pixel-based image classification, and is expected to provide novel, effective techniques for quantifying the spatial distribution and area of seagrass ecosystem worldwide. [ABSTRACT FROM AUTHOR]

Avoiding the worst impacts of global warming is a matter of systemic change and political will. An easily adaptable political system would be resilient to the effects of climate change, since a government could maintain effective control by implementing incremental changes. However, except for the United Kingdom (UK), Israel and New Zealand, all other states have rigid codified constitutions. Drawing on cybernetics and variety engineering, the study of New Zealand's constitutional system presented in this article suggests that a rigid codified constitution has merits for addressing long-term problems, such as climate change and sustainable development. [ABSTRACT FROM AUTHOR]