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There are nine

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science requirements for ICESat-2
when the mission was stood up

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initially, and all of those were mostly
for cryosphere science.

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One of those capabilities
was that the green wavelength

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of ICESat-2’s laser
altimeter does penetrate water.

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And no one really thought from 300 miles
in space that it would provide

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a real value added to nearshore
and coastal bathymetry, as an example.

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One of those products or efforts,
I should say,

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is to develop a global bathymetry product.

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And so that was ATL24.

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So what this product does is it takes the,

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geolocated point cloud data,
which is ATL03,

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and does a unique way of signal finding
and then classifying that signal

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these photons, detected photons,
as either sea surface

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or seafloor.

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And we do this globally in areas
that we know

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ICESat-2 has a has a high probability
of collecting bathymetric data.

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A lot of

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my work involves
mapping of nearshore areas and particular

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mapping of bathymetry, which means water
depths, and nearshore areas.

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And unfortunately, in areas
all over the world,

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we have a global nearshore data void,
which basically means

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we have these big gaps in coverage of
water depths near the near the shoreline.

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And so fortunately,

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ICESat-2 has proven remarkable
at measuring this nearshore bathymetry.

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In my work,
geospatial data products often include

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bathymetric digital elevation
models or DEMs.

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So these are models of seafloor elevation.

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And so although ICESat-2 wasn’t designed
initially for a bathymetric

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measurement--it was primarily designed
for measuring ice sheets, glaciers and sea

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ice--it really has proven to be great
at measurement of nearshore bathymetry

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and these other, nearshore,
you know, seafloor data products.

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So a lot of users of ICESat-2 bathymetry
are hydrographic surveying offices.

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And so these are offices
which are charged with surveying

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bathymetry and basically collecting data
that goes on to nautical charts.

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And these nautical charts are what
keep mariners safe at sea when they’re

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when they’re navigating at sea.

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And so

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some of the ways that hydrographic
survey offices can use ATL24,

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for example, if you’re getting ready
to send small boats into an area

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to do surveying in a place where
you just don’t have great existing data.

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This can potentially be dangerous,
particularly if you’re working in areas

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where there might be submerged
hazards, rocks, for example.

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I really think it’s important to,
to know that ATL24 is right now

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a product that gives you sea surface
and seafloor elevations

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at the native resolution of 70 centimeters
in the along track direction,

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but the way that we’re going to eventually
offer it to the community through SlideRule

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makes it so that you can customize
your bathymetry product.

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So SlideRule is a
what I call a web-based data service.

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At the core of SlideRule,
the idea that we have

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is that it is the idea
that it would be more efficient and better

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for NASA, better for the science
communities, if we distribute

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level-three and level-four
science data products as a service

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instead of a statically pre-generated
archival data set.

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And so scientists
then don’t have to work with the hundreds

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of terabytes of photon cloud data.

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They can work
with hundreds of gigabytes

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or gigabytes of the specific ice sheet
elevation

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data that that they want
for their investigation.

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And so that's where SlideRule comes
in, where we instead

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of distributing pre-generated static files,

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we are distributing in a sense
the algorithms.

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So they can ask hard questions
about a lot of data over a lot of time,

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using algorithms
that had a lot of time invested

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in them, sophisticated algorithms
and tuning it for their application.

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I think ICESat-2 with the expected
lifetime of being another

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maybe ten years based on
the level of consumables on board.

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It's it's poised to just be a component
of the Earth-observing system

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as a whole for a while,
and can be a validation capability

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in and of itself to other or new
missions that are launched.