The impact of climate change on the archaeology of New Zealand’s coastline

Abstract: With rising sea levels, changes in precipitation patterns and an increased incidence of severe weather events being predicted as a result of global climate change, the Department of Conservation commissioned a study to determine the potential impacts of these effects on New Zealand’s archaeological sites, which are mostly located near the coast. A Geographic Information System (GIS)-based case study examined the distribution of archaeological sites in the Whangarei District and assessed the risk to the archaeological resource primarily from sea level rise associated with future climate change.The results of the analysis are fairly conclusive. Currently, the major threats to archaeological sites in coastal areas are erosion, flooding and ground instability, and some sites are at risk from more than one of these threats. Approximately one-third of the recorded site locations in the Whangarei District are potentially threatened by these hazards, regardless of any future climate change effects. Climate change will exacerbate existing coastal hazards, and increase the likelihood and severity of impacts on archaeological sites. An additional 2.5–10% of archaeological sites might be affected by increased threats due to predicted changes in climate, including rising sea levels. The types of sites that are most likely to be affected in the Whangarei District are coastal midden and small habitation sites relating to Māori occupation. Although these could be affected by all three of the major hazards identified, they are particularly susceptible to coastal erosion. Land stability issues and flooding are likely to affect a greater range of sites, including larger sites such as pā and sites relating to early European settlement. It is not possible to quantify the risk to sites from increased land instability as a result of global climate change, but it is noted that any increase in extreme weather events would not be confined to coastal areas. These sites potentially hold significant information relating to the history of both the district and New Zealand. The implications of the study are that coastal sites are already under considerable threat, and that important archaeological information is being lost at a rate that may increase significantly in the future. Action is needed now to protect or retrieve the information from significant sites under threat in coastal areas before these sites disappear completely

A new chronology for the Māori settlement of Aotearoa (NZ) and the potential role of climate change in demographic developments

Understanding the role of climate change, resource availability, and population growth on human mobility remains critically important in anthropology. Researching linkages between climate and demographic changes during the short settlement history of Aotearoa (New Zealand) requires temporal precision equivalent to the period of a single generation. However, current modeling approaches frequently use small terrestrial radiocarbon datasets, a practice that obscures past Māori population patterns and their connection to changing climate. Our systematic analysis of terrestrial and marine 14C ages has enabled robust assessments of the largest dataset yet collated from island contexts. This analysis has been made possible by the recent development of a temporal marine correction for southern Pacific waters, and our findings show the shortcomings of previous models. We demonstrate that human settlement in the mid-late 13th century AD is unambiguous. We highlight early (AD 1250-1275) settlement in the North Island. The South Island was reached a decade later (AD 1280-1295), where the hunting of giant flightless moa commenced (AD 1300-1415), and the population rapidly grew. Population growth levelled off around AD 1340 and declined between AD 1380 and 1420, synchronous with the onset of the Little Ice Age and moa loss as an important food source. The population continued to grow in the more economically stable north, where conditions for horticulture were optimal. The enhanced precision of this research afforded by the robust analysis of marine dates opens up unique opportunities to investigate interconnectivity in Polynesia and inform the patterns seen in other island contexts

Environmental changes in oxygen tension reveal ROS-dependent neurogenesis and regeneration in the adult newt brain

Acknowledgements: We thank A Elewa, N Dantuma, C Sjögren for many helpful comments on the manuscript, and H Wang and M Kirkham for advice. This work was supported by grants from the European Research Council, Swedish Research Council, Swedish Cancer Society, AFA Insurances to AS. YC´s laboratory is supported by research grants from the Swedish Research Council, the Swedish Cancer Foundation, the Karolinska Institute Foundation, the Karolinska Institute distinguished professor award, the Torsten Soderbergs foundation, the NOVO Nordisk Foundation, the Advanced grant from the NOVO Nordisk foundation, and the Alice Wallenberg foundation This article is distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use and redistribution provided that the original author and source are credited.Peer reviewedPublisher PD

Light source selection for a solar simulator for thermal applications: A review

Solar simulators are used to test components and systems under controlled and repeatable conditions, often in locations with unsuitable insolation for outdoor testing. The growth in renewable energy generation has led to an increased need to develop, manufacture and test components and subsystems for solar thermal, photovoltaic (PV), and concentrating optics for both thermal and electrical solar applications. At the heart of any solar simulator is the light source itself. This paper reviews the light sources available for both low and high-flux solar simulators used for thermal applications. Criteria considered include a comparison of the lamp wavelength spectrum with the solar spectrum, lamp intensity, cost, stability, durability, and any hazards associated with use. Four main lamp types are discussed in detail, namely argon arc, the metal halide, tungsten halogen lamp, and xenon arc lamps. In addition to describing the characteristics of each lamp type, the popularity of usage of each type over time is also indicated. This is followed by guidelines for selecting a suitable lamp, depending on the requirements of the user and the criteria applied for selection. The appropriate international standards are also addressed and discussed. The review shows that metal halide and xenon arc lamps predominate, since both provide a good spectral match to the solar output. The xenon lamp provides a more intense and stable output, but has the disadvantages of being a high-pressure component, requiring infrared filtering, and the need of a more complex and expensive power supply. As a result, many new solar simulators prefer metal halide lamps

The Aotearoa/New Zealand Radiocarbon Database Upgrade

For the last 20 years, New Zealand researchers have had limited access to a large number of radiocarbon dates measured on archaeological materials. The most used resource containing this type of information, the NZ Radiocarbon Database (McFadgen et al. 2000), has not been updated since 2002, leaving researchers to create their own, often selective datasets for analysis (e.g., Bickler 2018a, 2019; Bickler et al. 2013; Brown 2014, Brown and Crema 2019, Wilmshurst et al. 2011). Consequently, many radiocarbon dates have fallen into obscurity. Here we introduce a new online geospatial database for NZ archaeological radiocarbon data that incorporates and adds to these older datasets. This project has identified over 5100 radiocarbon records associated with archaeological sites and artefacts, of which more than 4100, having met the minimum auditing requirements, are included in a new database release

Estimating parent population of pottery vessels from a sample of fragments: a case study from inter-tidal surface collections, Roviana Lagoon, Solomon Islands

Archaeologists frequently interpret the duration and type of prehistoric occupation at a location/site from the relative abundance of prehistoric materials (accumulations research). Taphonomic factors have the potential to alter substantially the archaeological record leading to inaccurate assumptions about the nature of prehistoric settlement. Where vessel families of potsherds can be established, we provide a general method to estimate the parent population from which the sample of sherds derives, through analysis of vessel completeness of the sample. This provides a basis for archaeological interpretation of the scale of discard represented at a location. The approach used has broad applicability to many archaeological settings where behavioural inferences are made from poorly preserved ceramic samples. Statistical analysis of a ceramic assemblage from Roviana Lagoon stilt villages indicates that most of the ceramic assemblage has been destroyed over time. An unexpectedly severe taphonomic regime is inferred for this relatively sheltered landlocked lagoon setting. Rather than marking an ephemeral occupation, estimating a parent ceramic population indicates instead that early stilt village sites in the Solomon Islands region were probably permanently occupied for several centuries. Results also suggest that the relative absence of recorded Lapita sites in the main Solomon Islands, and possibly elsewhere in Near Oceania may be a result of a harsh taphonomic regime for the remains of stilt village occupation