Involving citizens in the science of weather

New WMO Citizen Science guidance released


By Dr Marion Tan

November 2021


New Zealand based researchers – including RNC affiliated researchers – play an active role in international projects including the global High Impact Weather (HIWeather) project. Dr Marion Tan (Massey University) led a working group of scientists to develop the HIWeather Citizen Science Guidance Note for Weather, Climate, and Water Projects. The HIWeather Guidance Note intends to help individuals, groups, and agencies to gain interest and capacity to do citizen science. Published in October 2021, the Guidance Note can be accessed through the World Meteorological Organization (WMO) Library

The Guidance Note is part of the broader HIWeather project launched in 2016 by WMO and World Weather Research Programme (WWRP). The 10-year research project aims to improve weather-related hazard warnings. Prof David Johnston (Massey University) co-led HIWeather from 2016-2020, and currently Dr Sally Potter (GNS Science) co-leads with Prof Brian Golding of the UK Met Office. 


Prof David Johnston (Massey University) with Prof Qinghong Zhang (HIWeather International Coordination Office, Chinese Academy of Meteorological Sciences), Lisa McLaren (Massey University), Emily Campbell (Massey University) during the HIWeather Workshop in 2018 held in Beijing China.

To achieve the HIWeather project’s aim, HIWeather has five research themes and three cross-cutting flagship projects, one of which is the ‘HIWeather Citizen Science’ Project. The HIWeather Citizen Science Project was designed as a platform for sharing information and tools to help people gain interest and capacity to do citizen science in the weather space. The newly published HIWeather Guidance Note encourages individuals, groups and agencies to consider citizen science and outlines key questions to ask when developing new projects.


Lisa Murray (MetService) at Kaingaroa School on the Chatham Islands, 2021

Citizen contributed data can be used to fill in gaps specially in hard to reach or remoteplaces. Moreover, citizen science can help connect the public with science organisations and build capacities for communities towards their response to high impact weather. For example, the Kaingaroa School in Chatham Island has recently added its own weather station, which provides data to the WMO Global Weather Models in real-time. Citizen contributed data can help improve local weather forecasts thus enabling the community to make safer decisions around fishing and boating activities. Citizen science have the potential to improve HIWeather research significantly.

Aside from the Guidance Note, the HIWeather Citizen Science Project continues its work towards sharing and encouraging citizen science. Current initiatives include a special journal issue on citizen science and the demonstration project series – web stories on successful citizen science projects.


‘Where oh where is the data?’

Identifying data sources for hydrometeorological impact forecasts and warnings in Aotearoa New Zealand


By Sara Harrison

November 2021


Severe weather warnings help us to prepare and take action to protect ourselves and our properties from the impacts of these hazards. Notable historic events both within and outside of Aotearoa New Zealand have revealed gaps in how these warnings are communicated to, and understood by, target audiences. Impact Forecasts and Warnings are a new warning system that has been proposed to address some of these gaps by communicating what the weather will do (i.e., the impacts), along with what the weather will be. This would add meaning to the warnings and enable audiences to make appropriate decisions to protect themselves.


Credit: Dave Allen, NIWA

One challenge with implementing Impact Forecasts and Warnings is the lack of understanding around the underlying causes of the impacts caused by the severe weather hazards. This makes it difficult for meteorologists and other warning service providers to adequately forecast impacts in addition to the weather hazards. More data is needed to build this understanding and forecasting capability.

In this study, we conducted a series of interviews with users and creators in New Zealand of hazard, impact, vulnerability, and exposure data to identify data sources and understand how these data are collected and created. We found that many sources of data are used for emergency/disaster response and research purposes (these are the causal conditions for collecting these data, as shown in the figure below), that could potentially be repurposed for Impact Forecasts and Warnings.

However, some barriers to collecting and using these data for Impact Forecasts and Warnings. These are the intervening conditions shown in the figure. For example, misdirected/conflicting priorities of upper management and lack of motivation or interest inhibit data collection efforts. Furthermore, the leading mandate of warning services is to preserve life and property through accurate warning messages. As such, they must be able to trust the data the use to inform their decisions. Consequently, there is a preference to use official data (such as 111 calls, wellbeing surveys, etc.) over unofficial data sources such as social media, crowdsourcing. However, some of these official data sources are not available in real-time, which is a critical need for updating warnings as the event unfolds. These unofficial data sources (e.g., social media and crowdsourcing) offer more timely data but are considered less trustworthy than less timely official data sources. Thus, a tension exists between the timeliness and trustworthiness of the data needed for Impact Forecasts and Warnings, requiring warning services and other relevant agencies to compromise between these two factors.


Figure 1: The causal conditions, intervening conditions, and action/interaction strategies for collecting hazard, impact, vulnerability, and exposure data for impact forecasts and warnings. Causal conditions are the drivers of the data collection, intervening conditions are conditions that inhibit or facilitate the phenomena, and action/interactions strategies are strategies that were identified to address the intervening conditions.

Strategies were identified to address these intervening conditions. These are the action/interaction strategies listed in the above figure. Garnering support and buy-in on a data collection initiative can help redirect priorities and rejuvenate motivation and interest. Leadership from an individual or a community such as the NZGIS4EM group can also help with priorities and motivation. Quality control measures and standardised data collection methods can also be used to improve the trustworthiness of unofficial data so that it more useful for use in an Impact Forecasting and Warning system.

Additional work built off of these interviews is exploring the how these datasets can be used for Impact Forecasts and Warnings (Harrison et al., Under review), and further challenges to accessing and using them (Harrison et a., Submitted). Publications of this work are forthcoming.



Harrison, S. E., Potter, S. H., Prasanna, R., Doyle, E. E. H., & Johnston, D. (In Press). ‘Where oh where is the data?’: Identifying data sources for hydrometeorological impact forecasts and warnings in Aotearoa New Zealand. International Journal of Disaster Risk Reduction.

Harrison, S. E., Potter, S. H., Prasanna, R., Doyle, E. E. H., & Johnston, D. M. (Under Review). Identifying the data uses and gaps for severe weather impact forecasts and warnings. Weather, Climate, and Society.

Harrison, S. E., Potter, S. H., Prasanna, R., Doyle, E. E.-H., & Johnston, D. (Submitted). ‘Sharing is caring’: A socio-technical analysis of the sharing and governing of hydrometeorological impact data in Aotearoa New Zealand.


Impact case study:
Responsive science for national emergencies


September 2021

Once again, 2020-21 provided numerous opportunities for our researchers to provide high quality analysis, advice and public commentary as natural hazard events unfolded, and in the aftermath.

On the morning of September 18th, winds picked up in Auckland and an extreme gust measured at over 120km/hr blew two trucks sideways on the Harbour Bridge, seriously damaging the bridge structure. Several lanes were closed for weeks while repairs took place, leading to lengthy traffic delays and flow-on economic impacts.

Research carried out by NIWA as part of our Weather & Wildfire programme combined a computer model of wind patterns in the harbour with a three-dimensional model of the bridge and found the bridge itself causes the wind to speed up.

“The effects here are very localised and it is really important to understand these better because of the risk high wind events have to a range of assets such as transport and distribution networks and the potential knock-on to economic impacts,” said our Weather & Wildfire programme co-leader Dr Richard Turner in a media story. The research has demonstrated a potential tool that could be a component of a warning system that could halt traffic on the aging bridge and prevent a repeat incident. 

March 5 sequence. Credit: GNS Science

On the morning of March 5th, a M7.2 earthquake struck off the East Coast of the North Island, and an M7.4 and M8.1 followed soon after in the Kermadecs. The quakes triggered a tsunami alert for large parts of Aotearoa New Zealand. Our Earthquake & Tsunami programme co-leader Dr Bill Fry (GNS Science) provided science advice to the National Crisis Management Centre and explained the situation at the press conference fronted by Minister Allan.

The Earthquake & Tsunami team’s synthetic seismicity catalogue had previously been used to test the Tsunami Early Warning (TEW) system being developed under the aligned ‘Rapid Characterisation of Earthquakes and Tsunami’ Endeavour programme, also led by Bill Fry. On March 5th, Bill and other team members used a prototype of the TEW system to inform decision making during the response. Testing using the RNC synthetic catalogue gave the team confidence that the prototype TEW system was appropriate to base scientific advice on. This led to a much quicker input of advice supporting tsunami warning cancellation.

The NEMA post-event report recognised Fry’s contribution, stating: “There was recognised value in having a GNS Science representative (Fry) contributing to the media stand-ups to provide scientific context and advice, and to support the preparation of the Minister for Emergency Management and Acting Director CDEM.” The timing of the March 5 events also created significant interest in our scheduled webinar on the synthetic earthquake catalogue the following week.

Autumn 2021 saw record-breaking drought in parts of the country after an exceptionally dry 2020. Dr Nick Cradock-Henry of Manaaki Whenua Landcare Research, co-leader of our Resilience in Practice programme, has worked extensively with rural communities, agri-business groups and local and central government on natural hazard responses and resilience solutions. Focusing on climate change and drought, Nick’s research in North Canterbury and Marlborough has highlighted the need for applied resilience solutions, including improved monitoring and evaluation, climate services and targeted support. Both in the media, and in a well-attended webinar as part of our rolling symposium on drought (see Impact Case Study: Partnership as the Pathway to Impact), Nick provided informed commentary on the ways that drought can exacerbate existing social and economic vulnerabilities, and evidence-led solutions for drought-affected communities. 

On 28 May MetService issued a red alert for the Canterbury region forecasting 200-300 millimeters which they warned could cause significant flooding. An extreme rainfall event followed, causing extensive, damaging flooding in the South Canterbury area, and resulting in the declaration of a region-wide state of emergency from 30 May to 10 June.

Our researchers provided expert commentary on the floods. In particular, Asaad Shamseldin of The University of Auckland and our Built Environment team provided useful expertise on ‘atmospheric rivers’, how this phenomenon contributed to the devastating impacts in South Canterbury, and the increased frequency of atmospheric river events in a changing climate.


Damage from May 2021 flooding. Credit: Timaru District Council

There has also been public discussion on the description of such events as ‘a 1 in 100 year flood’ or similar, given underlying climate conditions are changing so rapidly. Prof Ilan Noy of Te Herenga Waka Victoria University of Wellington and our Multihazard Risk team, was on the ground in Westport during the devastating floods in July and critiqued this terminology and the false impression it creates regarding likely recurrence.


This case study was submitted to the Ministry of Business, Innovation and Employment as part of our 2020-21 annual reporting. 


The growing wildfire risk at the urban margins


By Gavin McCleave, science communications intern



Fires on the margins of urban areas in Aotearoa New Zealand have been relatively rare in the past but are becoming more common. Climate change is making the country hotter and drier, and land usage at the rural-urban interface (RUI) is rapidly changing as subdivisions are creating more than 5,000 new semi-rural sections every year. This is increasing the number of people and homes in the RUI, increasing the risk of wildfires starting, and increasing the risk of fires spreading into suburban areas.

This was demonstrated by the Port Hills wildfire in Christchurch in 2017. As described in 2018 research by Scion’s Lisa Langer and Simon Wegner, the nine destroyed homes were lifestyle properties, but the majority of the 450 homes threatened by the wildfire were within the urban fringe and city limits.

Fire mitigation for rural properties is well understood by local government and fire agencies and this knowledge has been passed to rural property owners and communities, but greater focus is now required on communities in the RUI.

The RNC Weather and Wildfire research programme is using new weather modelling technologies and methods to quantify the effects of a hypothetical wildfire breaking out in a subdivision on Mount Iron, near Wānaka.


Mt Iron subdivision at Wānaka. Credit: Phyllis, Flickr

The Mount Iron community was chosen because it is a suburban development in progress, and, being in Otago, is at high risk of wildfire as it has highly combustible fuels like mānuka, limited road access and water resources, periodic strong north-westerly winds, and increasingly dry summers. Mount Iron has already been struck by a wildfire, in January 2012.

Effective mitigation strategies to reduce the risk of physical damage to properties include actions by local government planners such as making building consents contingent on using fire-resistant building materials, and minimum site-spacing between buildings and flammable vegetation.

But the social aspects are just as important; for example ensuring affected communities know about the risk of wildfires occurring, how to reduce the likelihood and impact of wildfires, and what to do to save their lives and protect their properties in the event of a wildfire.

Research in 2019 co-authored by Lisa Langer describes wildfire experiences and actions by predominantly Māori residents during the 2011 Karikari Peninsula wildfire, and preparedness before and after the event. Researchers found that experiencing the fire encouraged most residents to become better prepared. Whānau and marae also helped to inform and support residents during and after the wildfire.

The paper provides useful recommendations for improving preparedness for wildfires and encouraging safe fire use in rural communities across New Zealand. The success of this study led to Scion social and kairangahau Māori researchers conducting a study with a hapū in the Hokianga to explore what a resilient hapū would look like and to contribute towards planning with Māori communities to reduce natural hazard risk. The Karikari study also helped shape other Scion-led social fire research on targeted protection against extreme fire. The combined research has helped inform Fire & Emergency New Zealand’s Māori engagement policy and contributed to their work with tangata whenua to build resilience of Māori communities.


Impact case study:

Model and tools for decision-making


How did Resilience Challenge research have an impact in 2019-2020?


Central to our mission to accelerate natural hazard resilience is the development of new models and tools to quantify hazards and impacts in more realistic ways, providing better assessments of resilience options to decision-makers.

Development of new models is iterative, requiring repeated testing and validation, and their application usually comes at the end of an extensive period of development. RNC is driving meaningful enhancements and innovations in this area, building on work in Phase 1, the Natural Hazards Research Platform, and leveraging existing New Zealand tools such as RiskScape and MERIT.

Updated hazard map for Whakapapa skifield. Credit: GNS Science

Earlier this year, Volcano programme research was integrated into updated hazard posters  for Turoa and Whakapapa skifields, as part of a collaboration with the Department of Conservation. Researchers were also commissioned by Ruapehu Alpine Lifts to produce a technical report on potential lahar hazard in the Whakapapa ski area. A new lahar simulation model, calibrated to previous lahars, was used to estimate the lahar footprint and impact for a range of scenarios. Results of the report have been used to develop safety measures for the new Sky Waka gondola.



Dr Nicky McDonald and colleagues from ME Research produced economic modelling utilising the MERIT (Measuring the Economics of Resilient Infrastructure Tool) capability developed in Phase 1, to assess the economic consequences of fuel outage scenarios following the Auckland-Marsden Point fuel pipeline failure. MERIT was applied to five disruption scenarios, which were then evaluated with and without mitigation options to better understand the impact of disruption and potential value of mitigation actions for New Zealand. The report was prepared for MBIE and findings also contributed to the Board of Inquiry into the 2017 Auckland Fuel Supply Disruption.

As part of our Coastal Flooding project led by Prof Karin Bryan (University of Waikato) and Dr Scott Stephens (NIWA), Dr Shari Gallop and Masters student Akuhata Bailey-Winiata (Te Arawa, Ngāti Tūwharetoa) carried out a summer project to determine the proximity of coastal marae (located within 2km of the coast) to coastal and river waterbodies. They found that 93% of coastal marae are located in the North Island; over 45% of coastal marae are within 200 meters of the coastline; and approximately 70% of coastal marae are located below 20 meters elevation relative to mean sea level. Data will be used as a baseline for determining risk and vulnerability of coastal marae to coastal hazards and sea-level rise. Akuhata’s research was recognised by the New Zealand Coastal Society who awarded him with a Māori and Pacific Island Research Scholarship in July 2020. 

Our Built Environment programme has completed new hazard maps for Bay of Plenty marae (showing fault lines, flooding, geothermal, liquefaction, and tsunami zones) using data from Rotorua City Council and Environment Bay of Plenty. The maps were provided to Te Arawa Lakes Trust collaborators, and are intended to be used to catalyse conversations with marae regarding adaptation and preparedness planning.

Part of our Weather and Wildfire programme involves the modelling of credible ‘what-if’ scenarios. What if the path of ex-Tropical Cyclone Cook (which did much damage in eastern Bay of Plenty in 2017) had been further west and hit our biggest population centre, Auckland? Weather scenario modelling at such fine-grid resolutions is a first for New Zealand, and allows detailed impact modelling to be carried out for a variety of coincident weather, flood, and landslide hazards, building a credible worse-case impact scenario for Auckland and surrounding districts. The early modelling is highlighting the potential for extreme impacts in Auckland, and in other areas well away from Auckland such as the higher elevations of the Kaimai ranges.


New modelling shows what could have happened if ex-TC Cook has tracked over Auckland. Credit: Ian Boutle, 2020

The primary goal of our Earthquake-Tsunami programme is to generate synthetic earthquakes using computer models. Big earthquakes and tsunamis (thankfully) don’t happen very often. A downside of this infrequency is that limited information from past earthquakes makes the job of forecasting future earthquakes and tsunamis challenging. One way of getting over these limitations is to generate synthetic earthquakes over millions of years using computer programs.

The team, led by Dr Bill Fry and Prof Andy Nicol, now has a first iteration of a synthetic seismicity model for New Zealand that incorporates all of the faults used for the National Seismic Hazard Model. This is a successful proof of concept. Further, through extended international collaboration, they have produced basic ground motion predictions from this model. This is an exciting and important stepping-stone in a programme of work that aims to improve future earthquake, tsunami and landslide hazard models in New Zealand.


This case study was submitted to the Ministry of Business, Innovation and Employment as part of our 2019-2020 annual reporting. 


High resolution ex-tropical cyclone modelling


What if ex-Tropical Cyclone Cook had hit Auckland?


By Dr Richard Turner

Many of the objectives of the Weather and Wildfire programme are highly dependent on creating ultra-high resolution, multi-hazard weather models. Part of the work involves the modelling of credible ‘what-if’ scenarios such as what if the path of ex-Tropical Cyclone Cook (which did much damage on the eastern Bay of Plenty coast) had been further west and hit Auckland.

To do this scenario modelling at such fine grid resolutions has not been done before in New Zealand and it will allow detailed impact modelling to be done for a variety of coincident weather, flood, and landslide hazards – building a credible worse-case impact scenario for Auckland and surrounding districts. 


Model images by Ian Boutle, 2020

The example plots above are some early results for Auckland, with the centre of ex-Tropical Cyclone Cook clearly evident offshore to the west of Auckland. It is interesting to note the extreme gust speeds in other areas well away from Auckland such as the higher elevations of the Kaimai Ranges – simulated to be well over 250 km/hr. For some more detail on the background to the ex-tropical cyclone modelling project there is an interesting NZ Herald article from January 2020 that is well worth a read.

At a recent workshop, presentations on the weather scenario (cyclones, fire, and winter storm) methodology, weather models, flood models, RiskScape (impact modelling) and data-sharing protocols were provided to interested researchers and modellers (coast, flood, landslide, and i-tool developers) within the Weather and Wildfire programme. For more information on the weather scenario modelling, contact Richard Turner.


Student Profile: Sara Harrison


Exploring the Data Needs for Impact-based Forecasting and Warning Systems in New Zealand




A bit about me 


I’m from Barrie, Ontario, Canada – a mid-sized city north of Toronto, in between the Great Lakes. We’re exposed to

 lots of active weather year-round. We experience white-out conditions from snowstorms in winter, and thunderstorms and the odd tornado in summer. Severe weather has always impacted my life, causing ‘snow-days’ due to rough winter roads, or outdoor soccer game cancellations due to risk of lightning strikes.

With a fascination for natural hazards and a love for reading and creating maps, I decided to study Geography at the University of Waterloo. For my honours thesis, I assessed the post-storm damage surveys conducted in Canada following potentially tornadic events. This sparked an interest in understanding how we could use crowdsourcing for disaster management, which I explored for my Masters of Environmental Studies (MES) degree, at the same university.

After completing my MES, I did some private GIS work but found that I preferred research. Fortunately, I met my current supervisor, Dr. Sally Potter from GNS, at the World Weather and Open Science Conference in Montreal just before starting my MES. We added each other on Facebook and three years later Sally posted a call for scholarship applications for a PhD project that aligned perfectly with my interests. The rest is history! In my spare time I enjoy rock climbing (bouldering), SCUBA diving, and travelling. 


My project


For my PhD I aim to map out existing and potential impact data sources from severe weather events in New Zealand to support a fairly new kind of warning system: impact-based forecasts and warnings. My guiding research question is: How is impact data currently collected, stored, and shared in New Zealand and how can this impact data support an impact-based forecasting and warning system?

In answering this question, I hope to identify current and potential sources of impact data for impact-based forecasts warnings and other applications like risk/impact modelling, response and recovery efforts, as well as challenges and opportunities in sharing the data and strengthening inter-agency collaborations for enhanced disaster risk reduction in New Zealand.

To do this, I’m interviewing people with expertise in creating, collecting, sharing, and using impact data for a variety of purposes including impact/risk modelling, severe weather warnings, and response. I’m using a grounded theory methodology to identify relationships and interdependencies between components in the impact-based forecasting and warning system and associated data infrastructure. I’m taking a sociotechnical approach so that I can explore both the social aspects of data creation, sharing, and use; along with the technical capabilities, limitations, and opportunities.

My research fits under the RNC2 Weather & Wildfire theme and aims to contribute to three efforts of the theme:

  • to help build national extreme weather hazards and impacts datasets,
  • to increase our understanding of impacts on communities, infrastructure, and economic activity, and
  • to improve the forecasting and warning services in New Zealand so that they provided more meaning to warning recipients.

My supervisors guiding me through this journey are Dr. Sally Potter (GNS), Dr. Raj Prasanna (Joint Centre for Disaster Research, Massey University), Dr. Emma Hudson-Doyle (Joint Centre for Disaster Research, Massey University), and Prof. David Johnston (Joint Centre for Disaster Research, Massey University).



Next steps


The expected outcome is to outline the process of getting impact data from the source (e.g. the public) to the end-users (e.g. Civil Defence groups, the MetService, impact/risk modellers, etc) for impact-based forecasts and warnings. This will help stakeholders understand what is available to them, and how they can access and contribute to it. Within a wider scope, this will support efforts towards meeting the requirements of the Sendai Framework to build a national impacts and losses database, as well as contribute to the implementation of impact-based forecasts and warnings in New Zealand.