Urgent Response Product Overview¶
NISAR is a powerful tool for monitoring surface dynamics, but most standard NISAR products are not made available until 36-72 hours after data acquisition.
NISAR Urgent Response (UR) products provide expedited processing in response to major events or natural disasters, such as earthquakes, volcanic activity, flooding, or wildfires. Acquisitions designated for UR data delivery will be flagged for rapid downlink and expedited processing to provide lower-latency data in support of response efforts.
UR products use lower-quality orbit ephemeris files for product processing than are used to process standard Production (PR) products, and do not have all atmospheric corrections applied. This may impact data quality, but allows the UR products to be made available much more quickly than PR products. Users should consider whether these tradeoffs are acceptable for their use case.
Acquisitions flagged for UR processing will still have PR products generated at the usual latency. UR products are retained in the archive for 30 days, after which only the PR products will be available.
Latency¶
Processing time for UR products varies based on product level, from 2 hours for Level 0 (raw) products to 6 hours for Level 2 (geocoded) products. Level 3 products are not generated as part of the UR workflow.
Refer to Table 1 for a comparison of data processing latency between PR and UR products.
Table 1:Processing time estimate comparisons for Production (PR) and Urgent Response (UR) products
| Product | PR Best Estimate | UR Best Estimate |
|---|---|---|
| L0 | 2-10 hours | 2 hours |
| L1 | 36-72 hours | 4 hours |
| L2 | 36-72 hours | 6 hours |
Tasking¶
NISAR UR tasking is initiated through a combination of automatic and manual requests. In most cases, UR products will be generated for acquisitions that are already in the reference observation plan. The acquisitions will simply be prioritized for downlink and flagged for expedited processing.
NISAR’s Smart Tasking Tool triggers UR requests automatically in response to:
Significant earthquakes
Earthquake with USGS Prompt Assessment of Global Earthquakes for Response (PAGER) level of Orange or Red
The epicenter of the earthquake is in the U.S. or India (or within 240 km of any border of these two countries) and has a PAGER level of Yellow
The epicenter of the earthquake is in the U.S. or India (or within 240 km of any border of these two countries) and is greater than 7.0 magnitude and less than 50 km deep
Volcanic events that trigger USGS Volcano Notifications for Aviation levels of Orange or Red
UR products can also be manually requested by authorized users at government agencies including USGS, NOAA, and NASA.
Non-Standard Acquisitions¶
The NISAR mission system is capable of providing revised scheduling for new acquisitions in response to an event or an event forecast notification, and delivering data on an expedited timeline.
This enables UR acquisitions over areas not covered by the standard observation plan (e.g., over the ocean), but this capability is expected to be exercised rarely. This option will be used when possible provided it does not interfere with planned maintenance or the base observation plan.
Naming Convention¶
UR products use the same naming conventions as standard NISAR products. They can be identified by the Product Identifier component, which is UR for Urgent Response instead of PR for Production.
Example RSLC UR product filename:
NISAR_L1_UR_RSLC_001_005_A_219_4020_SVNA_A_20220104T182346_20220104T183426_P01101_M_F_J_001.h5
Ancillary Data¶
UR products include lower precision orbit files and have fewer ancillary data layers than PR products. UR products are processed using Forecast Orbit Ephemera (FOE), which are preliminary predicted and lowest data quality of the Orbit Ephemeris Datasets. A comparison of ancillary data layers in Production and UR products is described in Table 2.
Table 2:Ancillary data layers available for Production (PR) and Urgent Response (UR) products
| Data Layer | PR Products | UR Products |
|---|---|---|
| Orbit Ephemeris | Near-Realtime Orbit Ephemeris (NOE) and Medium Orbit Ephemeris (MOE) | Forecast Orbit Ephemeris (FOE) |
| Radar Pointing | Near-Realtime Radar Pointing (NRP) and Precise Radar Pointing (PRP) | Forecast Radar Pointing (FRP) |
| Geolocation Correction using Ionospheric Total Electron Content | Yes | No |
| Tropospheric Correction | Yes | No |
Finding UR Products¶
UR products can be found using the same search and discovery mechanisms as PR products. UR products are available for 30 days, after which they are removed from the archive and only the standard PR products for that acquisition will be available.
Vertex¶
To search for UR products in Vertex, select Urgent Response under the Product Configuration filter in the Product Filters section, as shown in Figure 1.
Figure 1:Search for Urgent Response products in Vertex by selecting Urgent Response in the Product Configuration dropdown menu in the Product Filters section.
Earthdata Search¶
The easiest way to search for UR datasets in Earthdata Search is to type nisar_ur into the search bar. This will return only the NISAR UR collections in your search results.
Figure 2:Search for Urgent Response products in Earthdata Search by typing nisar_ur into the search bar.
Unlike the PR products, there is one NISAR UR collection for each product level, rather than a collection for each product type. As such, different product types may be included in each UR collection.