obspy-datacenter-client skill

---
name: obspy-datacenter-client
description: ObsPy allows you to easily download earthquake data from various data centers/networks through its client API. This is an overview of available services and a demo of the client API for International Federation of Digital Seismograph Networks (FDSN). Use this if you need to download earthquake research data.
---

# Retrieving Data from Data Centers

The most common use case is likely to download waveforms and event/station meta information. In almost all cases you will want to use the `obspy.clients.fdsn` module for this. It supports the largest number of data centers and uses the most modern data formats. There are still a number of reasons to choose a different module but please make sure you have one.

Read [obspy-client-fdsn.md](obspy-client-fdsn.md) for usage of the FDSN client API.

## The FDSN Web Services

### Basic FDSN Web Services

| Available Data Types | Format |
|---------------------|--------|
| Waveforms | MiniSEED and optionally others |
| Station Information | StationXML and Text |
| Event Information | QuakeML and Text |

**Note**: Not all data providers offer all three data types. Many offer only one or two.

If you want to requests waveforms, or station/event meta information **you will most likely want to use the** `obspy.clients.fdsn` **module**. It is able to request data from any data center implementing the [FDSN web service definitions](https://www.fdsn.org/webservices/). Example data centers include IRIS/ORFEUS/INGV/ETH/GFZ/RESIF/… - a curated list can be found [here](https://www.fdsn.org/webservices/datacenters/). As a further advantage it returns data in the most modern and future proof formats.

### FDSN Routing Web Services

If you don't know which data center has what data, use one of the routing services. ObsPy has support for two of them:

i. The [IRIS Federator](https://service.iris.edu/irisws/fedcatalog/1/).
ii. The [EIDAWS Routing Service](http://www.orfeus-eu.org/data/eida/webservices/routing/).


### FDSN Mass Downloader

If you want to download a lot of data across a number of data centers, ObsPy's mass (or batch) downloader is for you. You can formulate your queries for example in terms of geographical domains and ObsPy will download waveforms and corresponding station meta information to produce complete data sets, ready for research, including some basic quality control.


## IRIS Web Services

**Available Data Types and Formats:** Various

IRIS (in addition to FDSN web services) offers a variety of special-purpose web services, for some of which ObsPy has interfaces in the `obspy.clients.iris` module. Use this if you require response information in the SAC poles & zeros or in the RESP format. If you just care about the instrument response, please use the `obspy.clients.fdsn` module to request StationXML data which contains the same information.

The interfaces for the calculation tools are kept around for legacy reasons; internal ObsPy functionality should be considered as an alternative when working within ObsPy:

| IRIS Web Service | Equivalent ObsPy Function/Module |
|-----------------|----------------------------------|
| `obspy.clients.iris.client.Client.traveltime()` | `obspy.taup` |
| `obspy.clients.iris.client.Client.distaz()` | `obspy.geodetics` |
| `obspy.clients.iris.client.Client.flinnengdahl()` | `obspy.geodetics.flinnengdahl.FlinnEngdahl` |

## Earthworm Wave Server

| Available Data Types | Format |
|---------------------|--------|
| Waveforms | Custom Format |

Use the `obspy.clients.earthworm` module to request data from the [Earthworm](http://www.earthwormcentral.org/) data acquisition system.

## NERIES Web Services

This service is largely deprecated as the data can just as well be requested via the `obspy.clients.fdsn` module.

## NEIC

| Available Data Types | Format |
|---------------------|--------|
| Waveforms | MiniSEED |

The Continuous Waveform Buffer (CWB) is a repository for seismic waveform data that passes through the NEIC "Edge" processing system. Use the `obspy.clients.neic` module to request data from it.

## SeedLink

| Available Data Types | Format |
|---------------------|--------|
| Waveforms | MiniSEED |

To connect to a real time SeedLink server, use the `obspy.clients.seedlink` module. Also see the ObsPy Tutorial for a more detailed introduction.

## Syngine Service

| Available Data Types | Format |
|---------------------|--------|
| Waveforms | MiniSEED and zipped SAC files |

Use the `obspy.clients.syngine` module to download high-frequency global synthetic seismograms for any source receiver combination from the IRIS syngine service.