National Institute Of Water And Atmospheric Research Research Articles

Using weather data to predict the presence of Lucilia spp. on sheep farms in New Zealand

Flystrike remains an important animal health issue on New Zealand sheep farms. To date no useful predictive tool to assist farmers to develop control options has been available. The aim of this study was to use National Institute of Water and Atmospheric Research (NIWA) virtual climate station data in New Zealand to develop a weather-based model to accurately predict the presence of Lucilia spp. on sheep farms throughout New Zealand. Three LuciTrap® baited fly traps were positioned on each of eight sheep farms throughout New Zealand (5 in the North Island and 3 in the South Island). The traps were put out for both the 2018–2019 and 2019–2020 seasons. They were emptied each week and the flies morphologically identified; with the counts of Lucilia cuprina and L. sericata combined as Lucilia spp. The count data for Lucilia spp. for each week of trapping was transformed into a binary outcome and a generalised linear mixed effects models fitted to the data, with farm as a random effect. The dependent variable was Lucilia spp. flies caught, yes or no, and the independent variables were mean weekly climate variables from the nearest NIWA virtual climate station to that farm. The model was trained on the 2018–2019 catch data and tested on the 2019–2020 catch data. A cut point was identified which maximised the model's ability to correctly predict whether Lucilia spp. were present or not for the 2019–2020 catch data, and the sensitivity, specificity, accuracy, and area under the curve (AUC) of the model calculated. The final model included just 3 significant variables, mean weekly 10 cm soil temperature, mean weekly soil moisture index, and mean weekly wind speed at 10 m. Mean weekly 10 cm soil temperature accounted for 64.7% of the variance explained by the model, mean weekly soil moisture index 34.7% and mean weekly wind speed at 10 m only 0.6%. The results showed that the predictive model had a sensitivity of 0.93 (95% CI = 0.80–0.98) and a specificity of 0.75 (95% CI = 0.62–0.85), using a cut point for the probability of Lucilia spp. being present on farm = 0.383. This model provides New Zealand farmers with a tool which will allow them to know when Lucilia spp. flies will likely be present and thus more accurately plan their interventions to prevent flystrike.

Aerosol-related effects on the occurrence of heterogeneous ice formation over Lauder, New Zealand ∕ Aotearoa

Abstract. The presented study investigates the efficiency of heterogeneous ice formation in natural clouds over Lauder, New Zealand / Aotearoa. Aerosol conditions in the middle troposphere above Lauder are subject to huge contrasts. Clean, pristine air masses from Antarctica and the Southern Ocean arrive under southerly flow conditions, while high aerosol loads can occur when air masses are advected from nearby Australia. This study assesses how these contrasts in aerosol load affect the ice formation efficiency in stratiform midlevel clouds in the heterogeneous freezing range (−40 to 0 ∘C). For this purpose, an 11-year dataset was analyzed from a dual-wavelength polarization lidar system operated by National Institute of Water and Atmospheric Research (NIWA), Taihoro Nukurangi, at Lauder in collaboration with the National Institute for Environmental Studies in Japan and the Meteorological Research Institute of the Japan Meteorological Agency. These data were used to investigate the efficiency of heterogeneous ice formation in clouds over the site as a function of cloud-top temperature as in previous studies at other locations. The Lauder cloud dataset was put into context with lidar studies from contrasting regions such as Germany and southern Chile. The ice formation efficiency found at Lauder is lower than in polluted midlatitudes (i.e., Germany) but higher than, for example, in southern Chile. Both Lauder and southern Chile are subject to generally low free-tropospheric aerosol loads, which suggests that the low ice formation efficiency at these two sites is related to low ice-nucleating-particle (INP) concentrations. However, Lauder sees episodes of continental aerosol, more than southern Chile does, which seems to lead to the moderately increased ice formation efficiency. Trajectory-based tools and aerosol model reanalyses are used to relate this cloud dataset to the aerosol load and the air mass sources. Both analyses point clearly to higher ice formation efficiency for clouds which are more strongly influenced by continental aerosol and to lower ice formation efficiency for clouds which are more influenced by Antarctic/marine aerosol and air masses.

Income and floods in New Zealand

ABSTRACT Floods include some of the most frequent and costliest extreme weather events in Aotearoa New Zealand. Using data from Statistics New Zealand’s Integrated Data Infrastructure and Historical Weather Events Catalogue from the National Institute of Water and Atmospheric Research (NIWA), this study empirically investigates the impact of floods on individual income across the country. The study considered thirteen economically significant flood events and the income of all the Inland Revenue registered individuals between 2000 and 2019. The impact of floods on the affected individual’s annual income was assessed using panel regressions with individual and time-fixed effects. Despite the large floods-induced privately insured damages, floods had no significant impact on individual annual incomes from salary, wage, self-employment, and total income across various specifications.

Integration of wind and tidal turbines using spar buoy floating foundations

<abstract> <p>Floating platforms are complex structures used in deep water and high wind speeds. However, a methodology should be defined to have a stable offshore structure and not fail dynamically in severe environmental conditions. This paper aims to provide a method for estimating failure load or ultimate load on the anchors of floating systems in integrating wind and tidal turbines in New Zealand. Using either wind or tidal turbines in areas with harsh water currents is not cost-effective. Also, tidal energy, as a predictable source of energy, can be an alternative for wind energy when cut-in speed is not enough to generate wind power. The most expensive component after the turbine is the foundation. Using the same foundation for wind and tidal turbines may reduce the cost of electricity. Different environment scenarios as load cases have been set up to test the proposed system's performance, capacity and efficiency. Available tidal records from the national institute of Water and Atmospheric Research (NIWA) have been used to find the region suitable for offshore energy generation and to conduct simulation model runs. Based on the scenarios, Terawhiti in Cook Strait with 110 m water height was found as the optimized site. It can be seen that the proposed floating hybrid system is stable in the presence of severe environmental conditions of wind and wave loadings in Cook Strait and gives a procedure for sizing suction caisson anchors.</p> </abstract>

A global total column ozone climate data record

Abstract. Total column ozone (TCO) data from multiple satellite-based instruments have been combined to create a single near-global daily time series of ozone fields at 1.25∘ longitude by 1∘ latitude spanning the period 31 October 1978 to 31 December 2016. Comparisons against TCO measurements from the ground-based Dobson and Brewer spectrophotometer networks are used to remove offsets and drifts between the ground-based measurements and a subset of the satellite-based measurements. The corrected subset is then used as a basis for homogenizing the remaining data sets. The construction of this database improves on earlier versions of the database maintained first by the National Institute of Water and Atmospheric Research (NIWA) and now by Bodeker Scientific (BS), referred to as the NIWA-BS TCO database. The intention is for the NIWA-BS TCO database to serve as a climate data record for TCO, and to this end, the requirements for constructing climate data records, as detailed by GCOS (the Global Climate Observing System), have been followed as closely as possible. This new version includes a wider range of satellite-based instruments, uses updated sources of satellite data, extends the period covered, uses improved statistical methods to model the difference fields when homogenizing the data sets, and, perhaps most importantly, robustly tracks uncertainties from the source data sets through to the final climate data record which is now accompanied by associated uncertainty fields. Furthermore, a gap-free TCO database (referred to as the BS-filled TCO database) has been created and is documented in this paper. The utility of the NIWA-BS TCO database is demonstrated through an analysis of ozone trends from November 1978 to December 2016. Both databases are freely available for non-commercial purposes: the DOI for the NIWA-BS TCO database is https://doi.org/10.5281/zenodo.1346424 (Bodeker et al., 2018) and is available from https://zenodo.org/record/1346424. The DOI for the BS-filled TCO database is https://doi.org/10.5281/zenodo.3908787 (Bodeker et al., 2020) and is available from https://zenodo.org/record/3908787. In addition, both data sets are available from http://www.bodekerscientific.com/data/total-column-ozone (last access: June 2021).

Applying New Zealand’s risk tools internationally: Case studies from Samoa and Vanuatu

Decision makers require disaster risk management (DRM) tools to better prepare for and respond to emergencies, and for making sound land- use planning decisions. Risk tools need to incorporate multiple hazard and asset types, and have the versatility to adapt to local contexts. RiskScape is a natural hazards impact and loss modelling tool developed to support DRM related decision making in New Zealand. The RiskScape software has benefitted from over 10 years of research and development, and has been used for a diverse range of applications both in New Zealand and internationally. Experience and challenges in applying RiskScape beyond New Zealand are highlighted in this study through the tailoring of RiskScape for Pacific Island countries, as part of the Pacific Risk Tool for Resilience (PARTneR) project. PARTneR is a collaborative project between the National Institute of Water and Atmospheric Research (NIWA), GNS Science, the disaster management offices of Samoa and Vanuatu, and the Geoscience Division of the Pacific Community. RiskScape is applied through three demonstration case studies for each country, focused on prominent natural hazards.

Mapping Marine Biodiversity: Using Open Source GIS Tools to Visualise and Extract Collection Data

The National Institute of Water and Atmospheric Research (NIWA) in Wellington manages one of New Zealand’s Nationally Significant Taxonomic Collections and Databases. The NIWA Invertebrate Collection (NIC) maintains data for over 125,000 (and growing) marine invertebrate specimens from over 46,000 localities in New Zealand, the Ross Sea portion of the Antarctic and the wider South West Pacific. This data is managed using a Specify Software database. NIC managers are often requested to provide large data extracts from specific regions of the New Zealand zone for a variety of uses, from biodiversity checklists of benthic protected areas, to the environmental impact assessment of commercial activities on areas of seabed. Using a built-in query to extract relevant records based on geographic coordinates is straightforward for data constrained in a single square box, but requests for data are usually from within multiple polygons and require significant data grooming and refining once extracted to become useful. Using the open source GIS program Quantum-GIS (QGIS), we present a flexible and generic approach to map based access to collection databases. A direct OpenGIS Simple Features Reference Implementation Virtual Data Source (OGRVRT) link from the Specify database into QGIS was established so that a user can visualise the entire current collection holdings on a map. As changes are made to object data or new records are added these will update instantly on the map, which assists with immediate validation of data and prevents the need to re-export data. Collection object data fields can be added as required and labelled differentially to visualise patterns, and the data can either be exported to a file from selected areas using map tools, or can be used to produce publication quality maps. This is an ideal collection management tool for mapping and visualisation, which will improve the accuracy, access and use of the data.

GIS-Based Rainfall Estimator Evaluation and Interpolation Analysis Using ArcGIS

We have been always trying to predict the weather to minimize risk, produce strategy, and other decision making situation. To achieve this, monitoring method need to be used to gather data. Rainfall monitoring is one of the area that widely used and one of the mostly used method is satellite-based rainfall monitoring. However, there are limitation to apply to the Satellite Rainfall (SR) estimation specifically on its accuracy and lack of certainty. Thus, study that directed to measure the inaccuracies of SR measurements is needed by using data of distribution of Actual Rainfall (AR). The SR data is taken from the National Oceanic and Atmospheric Administration (NOAA)’s Hydro—Estimator while the AR data was from the National Institute of Water and Atmospheric Research (NIWA). Through the statistics and interpolation analysis using ArcGIS, the study shows a prominent result of SR estimation accuracy in the sample area and thus may opens up more similar implementation as well as stands as a good benchmark for future improvement of the method. This study also shows how interpolation method through a GIS software could provide a significant result on a geographical related studies. Keywords : GIS, Geospatial Analysis, Interpolation Analysis, Arcgis

Managing Data in the NIWA Invertebrate Collection: Past and Present Methodology

The National Institute of Water and Atmospheric Research (NIWA) Invertebrate Collection is a Nationally Significant Collection consisting of around 300,000 marine invertebrate specimen jars housed at the NIWA Greta Point campus in Wellington, New Zealand. Our collection holdings include samples from New Zealand, Antarctic and Pacific waters and represent over 70 years of collecting and is still growing. We estimate approximately 40% of our collections are registered and digitally accessible (about 127,000 records since digital registering began in 2004), with most of our unregistered material being historical collections. We are the repository for several important historical collections, one of the largest being the former New Zealand Oceanographic Institute (NZOI) collection, a taxonomically diverse and a geographically wide-ranging collection which occurred from the 1950’s to the early 1990’s. Associated specimen information such as station data and taxonomic identification for these historical collections are managed by NIWA staff and are in the form of Microsoft Excel and Access spreadsheets, NIWA and NZOI Biodiversity Memoirs, and online via the NIWA cruise and station database. These data are manually collated and registered into our Specify collections software specimen database which offers a unified and comprehensive data repository for our historical specimens, therefore greatly improving data accessibility. To expedite the availability of data and improve access to specimens for our users we are focusing on the registration of both important historical and taxonomic collections, and streamlining the registration of specimens in the field onboard NIWA's research vessel Tangaroa. Our field registration and curation techniques have been fine-tuned over the years and now we are capturing data directly into a shipboard copy of Specify in the sorting lab on the ship, printing labels with a thermal printer, and importing data back to our home version following the end of the voyage using Specify's Workbench feature. This process reduces the time spent double-handling specimens and entering data off paper record sheets and allows the capture of data directly into our database immediately after collection and sorting onboard the ship.

Evaluating the impacts of volcanic eruptions using RiskScape

RiskScape is a free multi-hazard risk assessment software programme jointly developed by GNS Science and the National Institute of Water and Atmospheric Research (NIWA) in New Zealand. RiskScape has a modular structure, with hazard layers, assets, and loss functions prepared separately. While RiskScape was originally developed for New Zealand, given suitable hazard and exposed asset information, RiskScape can be run anywhere in the world. Volcanic hazards are among the many hazards considered by RiskScape. We first present RiskScape’s framework for all hazards, and then describe in more detail the five volcanic hazards – tephra deposition, pyroclastic density currents, lava flows, lahars, and edifice construction/excavation. We describe how loss functions were selected and developed. We use a scenario example to illustrate not only how RiskScape’s volcanic module works but also how RiskScape can be used to compare across natural hazards.

Development of a southern oceanic air standard reference material.

In 2009, the United States Congress charged the National Institute of Standards and Technology (NIST) with supporting climate change research. As part of this effort, the Gas Sensing Metrology Group at NIST began developing new gas standard mixtures for greenhouse gas mixtures relevant to atmospheric measurements. Suites of gravimetrically prepared primary standard mixtures (PSMs) were prepared at ambient concentration levels for carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) in a dry-air balance. In parallel, 30 gas cylinders were filled, by the National Institute of Water and Atmospheric Research (NIWA) in Wellington, New Zealand, to high pressure from pristine southern oceanic air at Baring Head, New Zealand, and shipped to NIST. Using spectroscopic instrumentation, NIST analyzed the 30 cylinder samples for mole fractions of CO2, CH4, and N2O. Certified values were assigned to these mixtures by calibrating the instrumentation with the PSM suites that were recently developed at NIST. These mixtures became NIST Standard Reference Material (SRM) 1721 Southern Oceanic Air and are certified for ambient mole fraction, the first of their kind for NIST. The relative expanded uncertainties corresponding to coverage intervals with 95% probability are no larger than 0.06% of the certified values, representing the smallest uncertainties to date ever assigned to an NIST gas SRM.

Distributional records of Ross Sea (Antarctica) Tanaidacea from museum samples stored in the collections of the Italian National Antarctic Museum (MNA) and the New Zealand National Institute of Water and Atmospheric Research (NIWA).

Here we present distributional records for Tanaidacea specimens collected during several Antarctic expeditions to the Ross Sea: the Italian PNRA expeditions (“V”, 1989/1990; “XI”, 1995/1996; “XIV”, 1998/1999; “XIX”, 2003/2004; “XXV”, 2009/2010) and the New Zealand historical (New Zealand Oceanographic Institute, NZOI, 1958-1961) and recent (“TAN0402 BIOROSS” voyage, 2004 and “TAN0802 IPY-CAML Oceans Survey 20/20” voyage, 2008) expeditions. Tanaidaceans were obtained from bottom samples collected at depths ranging from 16 to 3543 m by using a variety of sampling gears. On the whole, this contribution reports distributional data for a total of 2953 individuals belonging to 33 genera and 50 species. All vouchers are permanently stored in the Italian National Antarctic Museum collection (MNA), Section of Genoa (Italy) and at the National Institute of Water and Atmospheric Research (NIWA Invertebrate Collection), Wellington (New Zealand).

Designing a Wireless Sensors Network for Monitoring and Predicting Droughts

Abstract Global warming and lack of rain were the main problems that caused increased drought around the world. In New Zealand, according to National Institute of Water and Atmospheric Research (NIWA) the drought in 2012 and 2013 was the worst drought in the last 70 years. Therefore, there is a need for technological intervention to monitor basic information about the weather and soil condition in order to identify and predict drought conditions. Initial experiments have shown that the proposed wireless sensor drought monitoring system is capable of remote real-time monitoring for extended periods. This monitoring can also help identify drought in the early stages and thereby indicate promptly when to take corrective measures. Intelligent sensors in a wireless network monitor the soil condition. These sensors collect various environmental; parameters and then send the pre-processed data wirelessly to a base station. From the base station this data uploads every two seconds to the cloud (internet) for further analysis. If a drought condition is identified by the monitoring system then an alert message is sent to the user via text message or email.

Non-Gaussian larval dispersal kernels in Gaussian ocean flows

AB Aquatic Biology Contact the journal Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections AB 16:203-208 (2012) - DOI: https://doi.org/10.3354/ab00466 FEATURE ARTICLE Non-Gaussian larval dispersal kernels in Gaussian ocean flows Stephen M. Chiswell* National Institute of Water and Atmospheric Research (NIWA), PO Box 14-901, Kilbirnie, Wellington, New Zealand *Email: s.chiswell@niwa.cri.nz ABSTRACT: Models of larval dispersal in which ocean currents are Gaussian-distributed provide analytical solutions for the dispersal kernel that are usually assumed to be Gaussian-distributed as well. However, such Gaussian solutions are only valid for a single value of the duration of the larval period. In reality, larvae have a settlement competency period that can range from minutes to >1 yr. Dispersal kernels computed for larvae having a competency period of finite length become non-Gaussian, because later settlers contribute proportionately more to both tails of the kernels than early settlers. In species where the variability in larval duration is large, or mean flows are large compared to the variability, the dispersal kernels approach uniform rather than Gaussian distributions. KEY WORDS: Larval dispersal · Spatial kernels · Connectivity Full text in pdf format Information about this Feature Article NextCite this article as: Chiswell SM (2012) Non-Gaussian larval dispersal kernels in Gaussian ocean flows. Aquat Biol 16:203-208. https://doi.org/10.3354/ab00466 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in AB Vol. 16, No. 3. Online publication date: September 05, 2012 Print ISSN: 1864-7782; Online ISSN: 1864-7790 Copyright © 2012 Inter-Research.

Honors

Several AGU members were among the winners of the New Zealand Prime Minister's Science Prizes, announced on 16 December. The top award, which is called the Prime Minister's Science Prize and includes $500,000, is being given to a team of scientists with the National Institute of Water and Atmospheric Research (NIWA) and with the University of Otago, Dunedin, New Zealand, led by Philip Boyd, director of the NIWA Center for Chemical and Physical Oceanography. Members of the team include Russell Frew, professor in the University of Otago chemistry department, and Keith Hunter, the university's pro‐vice‐chancellor of sciences. The scientists have carried out some of the largest experiments ever undertaken to better understand the role the ocean plays in influencing climate. “The work has positioned New Zealand as a leader in [the] debate about whether manipulating the oceans to remove carbon dioxide emission from the air could mitigate or solve global warming,” according to a press release.

Extreme ozone loss over the Northern Hemisphere high latitudes in the early 2011

ABSTRACTThe satellite ozone data comprising The New Zealand National Institute of Water and Atmospheric Research (NIWA) total ozone database version 2.7, total ozone by the Ozone Monitoring Instrument (OMI) spectrophotometer on the Aura platform, and the ozone mixing ratios by SBUV/2 measurements on The National Oceanic and Atmospheric Administration (NOAA) platforms are analysed for ozone variability over the sunlit part of the Northern Hemisphere polar region. An extended area, with unusually low ozone values, is observed in a two-month period beginning in mid February 2011. The total area with extremely depleted total ozone reached the maximum at the end of March 2011, equal to ~11×106 km2. The area is even larger in the lower/mid stratosphere. A multiple regression model is proposed to attribute the polar total ozone variability to various chemical and dynamical ozone forcings. The model reproduces the ozone loss in early 2011 and the overall picture of the ozone long-term changes. The extreme ozone decline in 2011 could be attributed to the long-lasting period with low stratospheric temperature (<195 K), weaker than the normal Brewer-Dobson circulation, and the Arctic Oscillation in a strong positive phase. A deficit of total ozone in the following summer months (June–July–August), after the total ozone decline in March, was predicted and supported by later OMI observations.

Marine Biodiversity of Aotearoa New Zealand

The marine-biodiversity assessment of New Zealand (Aotearoa as known to Māori) is confined to the 200 nautical-mile boundary of the Exclusive Economic Zone, which, at 4.2 million km2, is one of the largest in the world. It spans 30° of latitude and includes a high diversity of seafloor relief, including a trench 10 km deep. Much of this region remains unexplored biologically, especially the 50% of the EEZ deeper than 2,000 m. Knowledge of the marine biota is based on more than 200 years of marine exploration in the region. The major oceanographic data repository is the National Institute of Water and Atmospheric Research (NIWA), which is involved in several Census of Marine Life field projects and is the location of the Southwestern Pacific Regional OBIS Node; NIWA is also data manager and custodian for fisheries research data owned by the Ministry of Fisheries. Related data sources cover alien species, environmental measures, and historical information. Museum collections in New Zealand hold more than 800,000 registered lots representing several million specimens. During the past decade, 220 taxonomic specialists (85 marine) from 18 countries have been engaged in a project to review New Zealand's entire biodiversity. The above-mentioned marine information sources, published literature, and reports were scrutinized to give the results summarized here for the first time (current to 2010), including data on endemism and invasive species. There are 17,135 living species in the EEZ. This diversity includes 4,315 known undescribed species in collections. Species diversity for the most intensively studied phylum-level taxa (Porifera, Cnidaria, Mollusca, Brachiopoda, Bryozoa, Kinorhyncha, Echinodermata, Chordata) is more or less equivalent to that in the ERMS (European Register of Marine Species) region, which is 5.5 times larger in area than the New Zealand EEZ. The implication is that, when all other New Zealand phyla are equally well studied, total marine diversity in the EEZ may be expected to equal that in the ERMS region. This equivalence invites testable hypotheses to explain it. There are 177 naturalized alien species in New Zealand coastal waters, mostly in ports and harbours. Marine-taxonomic expertise in New Zealand covers a broad number of taxa but is, proportionately, at or near its lowest level since the Second World War. Nevertheless, collections are well supported by funding and are continually added to. Threats and protection measures concerning New Zealand's marine biodiversity are commented on, along with potential and priorities for future research.

Synopsis of a new collection of sea spiders (Arthropoda: Pycnogonida) from the Ross Sea, Antarctica

The biodiversity research expedition TAN0204 with RS Tangaroa to the Ross Sea in 2004 yielded a new collection of 2,687 specimens of pycnogonids. As much as 25 different species encompassing 14 genera and eight families were identified and their records are discussed herein. The collection is archived in the Marine Invertebrate Collection of the New Zealand National Institute of Water and Atmospheric Research (NIWA). The majority (69%) of specimens are from the Nymphon australe group (Nymphonidae), although species richness and abundance varied among the stations sampled. The collection includes several specimens from polymerous taxa; Pentanymphon antarcticum (Nymphonidae), Decolopoda australis (Colossendeidae) and Pentapycnon bouvieri (Pycnogonidae). All species were classified based on morphological characters, and DNA sequences (from the 18S, 12S, 16S and COI regions) for 21 of the representative morphotypes are given. The DNA sequences confirmed the species-level distinctiveness of these morphotypes. No species new to science were identified, although further detailed morphometric and/or molecular analyses may reveal cryptic or sibling species, especially in species such as the highly abundant Nymphon australe group.

Predicting and monitoring the effects of large-scale ocean iron fertilization on marine trace gas emissions

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 364:283-288 (2008) - DOI: https://doi.org/10.3354/meps07549 Contribution to the Theme Section ‘Implications of large-scale iron fertilization of the oceans’ Predicting and monitoring the effects of large-scale ocean iron fertilization on marine trace gas emissions C. S. Law* National Institute of Water and Atmospheric Research (NIWA), Evans Bay Parade, Private Bag 14-901, Kilbirnie, Wellington 6241, New Zealand *Email: c.law@niwa.co.nz ABSTRACT: Large-scale (>40000 km2, >1 yr) ocean iron fertilization (OIF) is being considered as an option for mitigating the increase in atmospheric CO2 concentrations. However OIF will influence trace gas production and atmospheric emissions, with consequences over broad temporal and spatial scales. To illustrate this, the response of nitrous oxide (N2O) and dimethylsulphide (DMS) in the mesoscale iron addition experiments (FeAXs) and model scenarios of large-scale OIF are examined. FeAXs have shown negligible to minor increases in N2O production, whereas models of long-term OIF suggest significant N2O production with the potential to offset the benefit gained by iron-mediated increases in CO2 uptake. N2O production and emission will be influenced by the magnitude and rate of vertical particle export, and along-isopycnal N2O transport will necessitate monitoring over large spatial scales. The N2O–O2 relationship provides a monitoring option using oxygen as a proxy, with spatial coverage by Argo and glider-mounted oxygen optodes. Although the initial FeAXs exhibited similar increases (1.5- to 1.6-fold) in DMS, a subsequent sub-arctic Pacific experiment observed DMS consumption relative to unfertilized waters, highlighting regional variability as a complicating factor when predicting the effects of large-scale OIF. DMS cycling and its influence on atmospheric composition may be studied using naturally occurring blooms and be constrained prior to OIF by pre-fertilization spatial mapping and aerial sampling using new technologies. As trace gases may have positive or negative synergistic effects on atmospheric chemistry and climate forcing, the net effect of altered trace gas emissions needs to be considered in both models and monitoring of large-scale OIF. KEY WORDS: Iron fertilization · Trace gases · Nitrous oxide · Dimethlysulphide · Remineralization Full text in pdf format PreviousNextCite this article as: Law CS (2008) Predicting and monitoring the effects of large-scale ocean iron fertilization on marine trace gas emissions. Mar Ecol Prog Ser 364:283-288. https://doi.org/10.3354/meps07549Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 364. Online publication date: July 29, 2008 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2008 Inter-Research.

Spectral UV Measurements of Global Irradiance, Solar Radiance, and Actinic Flux in New Zealand: Intercomparison between Instruments and Model Calculations

Abstract Presented here are the results of a short but intense measurement campaign at Lauder, New Zealand, in which spectral irradiance from instruments operated by the National Institute of Water and Atmospheric Research (NIWA) and Austria/Innsbruck (ATI) were traced to different irradiance standards and compared. The observed spectral differences for global irradiance were relatively small (&amp;lt;5%) and were consistent with those expected from observed differences in the radiation standards used by each group. Actinic fluxes measured by both groups were also intercompared and found to agree at the 10% level. The ATI instrument had the additional capability of measuring solar direct beam irradiance and sky radiances. These provided the first series of sky radiance measurements at this pristine Network for the Detection of Atmospheric Composition Change (NDACC) site. The polarization of sky radiance results were compared with estimates from a radiative transfer model without any aerosols and was found to be up to 25% smaller. Total ozone values derived from Total Ozone Mapping Spectrometer (TOMS), Dobson measurements by NIWA, spectral direct sun measurements by ATI, and spectral global irradiance measurements by NIWA agreed generally within 2%–3%.