@@ -90,13 +90,13 @@ In the remainder of this chapter, we will primarily focus on the data
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volume challenge, in particular exploring how different decisions about
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data storage formats and layouts enable (or constrain) us as we attempt
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to work with data at large scale. We'll formalize a couple of concepts
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- we've alluded at throughout the course, introduce a few new
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+ we've alluded to throughout the course, introduce a few new
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technologies, and characterize the current state of best practice --
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with caveat that this is an evolving area!
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## Cloud optimized data
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- As we've seen, when it comes global and even regional environmental
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+ As we've seen, when it comes to global and even regional environmental
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phenomena observed using some form of remote-sensing technology, much of
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our data is now _ cloud-scale_ . In the most basic sense, this means many
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datasets -- and certainly relevant collections of datasets that you
@@ -117,7 +117,7 @@ be beneficial when the compute platform is "near" the data, reducing
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network and perhaps even I/O latency. However, to the extent that
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realizing these benefits may require committing to some particular
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commercial cloud provider (with its associated cost structure), this may
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- or may not be desirable change.
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+ or may not be a desirable change.
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:::
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Practically speaking, accessing data in the cloud means using HTTP to
@@ -173,7 +173,7 @@ Geospatial Consortium
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(OGC)] ( https://www.ogc.org/announcement/cloud-optimized-geotiff-cog-published-as-official-ogc-standard/ )
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in 2023. However, COGs _ are_ GeoTIFFs, which have been around since the
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1990s, and GeoTIFFs are TIFFs, which date back to the 1980s. Let's work
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- our way through this linage .
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+ our way through this lineage .
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First we have the original ** TIFF** format, which stands for Tagged Image
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File Format. Although we often think of TIFFs as image files, they're
@@ -227,7 +227,7 @@ the same compressed tile.
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A set of overviews (lower resolution tile pyramids) are computed from
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the main full resolution data and stored in the file, again following a
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- tiling scheme and and arranged in order. This allows clients to load a
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+ tiling scheme and arranged in order. This allows clients to load a
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lower resolution version of the data when appropriate, without needing
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to read the full resolution data itself.
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:::
@@ -261,7 +261,7 @@ particular desired subset of the image at a particular resolution
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the desired bounding box into pixel coordinates, then identifying which
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tile(s) in the COG intersect with the area of interest, then determining
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the associated byte ranges of the tile(s) based on the metadata read in
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- teh first step. And the best part is that "client" here refers to the
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+ the first step. And the best part is that "client" here refers to the
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underlying software, which takes care of all of the details. As a user,
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typically all you need to do is specify the file location, area of
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interest, and desired overview level (if relevant)!
@@ -286,7 +286,7 @@ configuration (shape) optimized for expected usage patterns. This
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enables a client interested in a subset of data to retrieve the relevant
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data without receiving too much additional unwanted data. In addition,
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chunk layout should be such that, under expected common usage patterns,
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- proximal chunks are morely likely to be requested together. On average,
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+ proximal chunks are more likely to be requested together. On average,
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this will reduce the number of separate read requests a client must
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issue to retrieve and piece together any particular desired data subset.
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In addition, chunks should almost certainly be compressed with a
@@ -339,7 +339,7 @@ choice of how to break the data into separately compressed and
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addressable subsets is now decoupled from the choice of how to break the
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data into separate files; a massive dataset can be segmented into a very
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large number of small chunks without necessarily creating a
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- correspondingingly large number of small individual files, which can
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+ correspondingly large number of small individual files, which can
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cause problems in certain contexts. In some sense, this allows a Zarr
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store to behave a little more like a COG, with its many small,
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addressable tiles contained in a single file.
@@ -640,8 +640,8 @@ our own custom multidimensional data array from a large collection of
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data resources that themselves be arbitrarily organized with respect to
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our specific use case.
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- Interested in learning more about STAC? If so, head over the [ STAC
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- Index] ( https://stacindex.org/ ) , and online resource listing many
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+ Interested in learning more about STAC? If so, head over to the [ STAC
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+ Index] ( https://stacindex.org/ ) , an online resource listing many
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published STAC catalogs, along with various related software and
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tooling.
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@@ -661,7 +661,7 @@ structured netCDF and GeoTIFF files -- historically successful and
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efficiently used in local storage, but often suboptimal at cloud scale.
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The second represents simple, ad hoc approaches to splitting larger data
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into smaller files, thrown somewhere on a network-accessible server, but
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- without efficiently readable overaching metadata and without any optimal
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+ without efficiently readable overarching metadata and without any optimal
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structure. The next two represent cloud optimized approaches, with data
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split into addressable units described by up-front metadata that clients
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can use to efficiently access the data. The first of these resembles a
@@ -694,7 +694,7 @@ use of external metadata -- whether as Zarr metadata or STAC catalogs --
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that allows clients to issue data requests that "just work"
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regardless of the underlying implementation details.
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- As a final takeway , insofar as there's a community consensus around the
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+ As a final takeaway , insofar as there's a community consensus around the
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best approaches for managing data today, it probably looks something
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like this:
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@@ -703,7 +703,7 @@ like this:
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cloud
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- ** Zarr stores** (with intelligent chunking and sharding), potentially
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referenced by STAC catalogs, as the go-to approach for storing and
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- provisioing multidimensional Earth array data in the cloud
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+ provisioning multidimensional Earth array data in the cloud
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- ** Virtual Zarr stores** , again potentially in conjunction with STAC
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catalogs, as a cost-effective approach for cloud-enabling many legacy
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data holdings in netCDF format
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