Environmental Reporting, Ministry for the Environment and Statistics New Zealand
"Lightning is the discharge of electricity, from thunderstorms, that equalises areas of positive and negative charge, for example, between a storm cloud and the ground. Thunderstorms form as a result of rapidly rising air with a high moisture content (humidity). On average, 1 in 10 lightning discharges strikes the ground (or sea) (Metservice, 2015). Lightning (and therefore thunderstorms) are also often associated with other severe weather events, such as strong wind gusts, and in extreme cases tornadoes.
By international standards, lightning does not occur frequently around New Zealand. However, thunderstorms, and thus lightning, can cause injury and damage (Ministry of Civil Defence and Emergency Management, 2010), and may increase in frequency and intensity with climate change (Mullen et. al., 2011).
This data shows the average annual number of lightning strikes per 25km square.
This dataset relates to the ""Lightning"" measure on the Environmental Indicators, Te taiao Aotearoa website.
Further information can be found in:
MetService (nd). Lightning observation services. Accessed 3 June 2015 from www.metservice.com.
Ministry of Civil Defence and Emergency Management (2010). Thunderstorms. Working from the same page: Consistent messages for CDEM (p3). Available from www.civildefence.govt.nz.
Mullan, B, Carey-Smith, T, Griffiths, G, & Sood, A (2011). Scenarios of storminess and regional wind extremes under climate change. NIWA Client Report: WLG2010-31 (pvii). Available from www.niwa.co.nz."
Data courtesy Transpower New Zealand Limited
Method: "The number of lightning ground strikes is recorded by the New Zealand Lightning Detection Network (NZLDN), owned by Transpower and run by MetService. Sensors around the country detect lightning over the New Zealand land mass and a short distance out to sea. These sensors detect very accurately the electrical discharge, location, and time, as well as noting other parameters such as current strength. The NZLDN records both cloud-to-cloud and cloud-to-ground strikes. Generally, the location of cloud-to-ground strikes can be determined to within approximately 1km. Data is from September 2000 – December 2014. The accuracy of the data source is of high quality. "