Data Blog

Access to Manually Collected Volcano Data is Moving from the FITS API to the Tilde API

Published: Tue Jan 16 2024 9:00 AM
Data Blog

Welcome, haere mai to another GeoNet Data Blog. Today’s blog is a little bit different. We are going to give some details about how we are changing access to one of our data sets, manually collected volcano data.

While you might wonder why a blog is required for such a specific, and by volume small, data set. The user group for the data set is different from some of our other data, and the change is accompanied by some differences behind the scenes that we think deserve being explained.

What does it mean?

  • Manually collected volcano data or manualcollect refers to GeoNet data that are collected “by hand”. A common example is that a GeoNet specialist travels to a location and measures the temperature of a hot spring. In this context, “manualcollect” is known as a “data domain”. A domain is a broad data collection method or discipline. Within GeoNet, almost all manualcollect data are collected by the Volcano Monitoring Group (VMG) in their routine volcano monitoring work.

  • FITS is GeoNet’s Field Time Series database and data delivery application. Manually collected volcano data first started to be available through FITS around 2015. FITS has now passed it’s “use by” date and is progressively being replaced by the Tilde application.

  • Tilde is our new-ish application for delivering lower rate (typically collected less frequently than once a second) data to our users. Tilde already provides DART, coastal tsunami gauge, and envirosensor data, and is the obvious new home for manualcollect data.

  • An API (Application Program Interface) is a technical term used to mean an agreed set of instructions (or language) between a computer application and some other application. If you are accessing GeoNet data, you can simply think of it as the online application you use.

When is it happening?

The data were copied in November, and for the moment, you can access all the data through both FITS and Tilde applications. But our plan is to turn off FITS access to manually collected volcano data on 31 March 2024.

Until then, we plan to load all new data into both FITS and Tilde, so you should get the same results no matter which you query. Though we suggest you don’t leave the switch to the last minute and get started with Tilde now, if you haven’t already given it a go.

What’s included and what’s not

Manually collected volcano data isn’t as clearly defined as we’ve so far suggested. Here are a few examples of what is, and is not, included in the move.


  • Laboratory analysis of the composition of water from samples from volcanic hot springs, lakes, and streams.

  • Emission rates of gases from volcanoes that are measured flying around the volcano in a light plane, followed by analysis back in the office.

  • Slow vertical ground movement changes around the shore of Lake Taupō. These data are collected four times a year using a portable water level gauge. Incidentally, this data set was very valuable when we experienced volcanic unrest at Lake Taupō in 2022-23.


Excluded data are essentially all volcano data currently available through FITS that are not manually collected.

  • Water level and temperature at Te Wai ā-moe (Ruapehu Crater Lake). These data are collected by a data logger, which is why they are excluded. When we renew the data collection here, the new data will automatically be available in Tilde through the envirosensor domain.

  • Volcanic sulphur dioxide (SO2) emission rates collected by scanDOAS instruments. When we later migrate these to Tilde, it will probably be as their own data domain.

Static image plotting is out of scope

While Tilde is a replacement for FITS, it’s not an exact swap. There’s a feature offered by FITS that we’ve chosen not to make available in Tilde, the provision of Scalable Vector Graphics (SVG) format graphs of data as a static image. We surveyed our FITS users, and few said that was critical for their work given what Tilde and other applications now offer. Instead, we are going to provide a “click and select” data viewing application that gives users the ability to share graphs with others. This is coming soon.

Behind the scenes benefits

Perhaps the biggest gain from moving from FITS to Tilde for manually collected volcano data is the requirement to have all the data collection site information in GeoNet’s Delta meta-data database. This is required because Tilde relies on Delta to know what data are collected as well as where and when they were collected. FITS didn’t use Delta so manual collection site information wasn’t previously available there. Adding these has required some hard thinking as the idea of a place where you manually collect data is a little different from somewhere where an instrument sits and automatically collects data. But after a few tweaks we got there.

Meta-data for collecting volcano data now conforms to GeoNet’s data standards for the first time since GeoNet started in 2001. This opens up the opportunity for our data users to understand volcano data collection as well as all the other data GeoNet collects. We think this is a really big step forward.

Helping with the changeover

We’ve got some material to help with the changeover from FITS to Tilde. The Tilde API isn’t the same as the FITS API, so a FITS URL (web link) to retrieve data won’t work with Tilde. We also changed a few “station codes” and the names used to describe the different kinds of data. Tilde has given us more flexibility to work around some of the quirks of volcano manualcollect localities, and we’ve tried to have the style of data type names consistent across all data domains in Tilde.

Your first port of call should be our Tilde data access tutorials. These will give you an idea of how to get data (and meta-data) from Tilde. If you need the technical Tilde API information, we have a page on that too. The easiest way to work out what URL will give you the data you need is the Tilde Data Discovery GUI, as the URL produced by your “click and select” is shown on your web browser screen. Finally, we have a long list showing each FITS URL and the equivalent Tilde URL.

If none of that works and you are completely stuck, email us at Please put “FITS to Tilde migration” in the subject line.

That’s it for now

While FITS has been useful, especially for manualcollect volcano data, Tilde offers many advantages. Please start your own transition sooner rather than later so you are not rushing before the 31 March 2024 deadline. You can always reach out to us if you are stuck. You can find our earlier blog posts through the News section on our web page just select the Data Blog filter before hitting the Search button. We welcome your feedback on our data blogs and if there are any GeoNet data topics you’d like us to talk about please let us know! Ngā mihi nui.