# Presentation: 912805

## NOAA Lab for Satellite Altimetry Global Sea Level Rise R&D Program 

-   Altimeter/Tide Gauge calibration project
-   Re-analysis of altimetric record  -- connecting GEOSAT to TOPEX
-   Historical analysis from tide gauge & hydrographic observations
-   Preparing for Jason-2/OSTM (2008 launch) ... Four Party Mission                  NASA/CNES with NOAA & EUMETSAT junior partners
-   Planning/Gaining Approval for Jason-3 (2013)  ... NOAA & EUMETSAT Proposed Lead Agencies.

- NOAA Lab for Satellite Altimetry Global Sea Level Rise R&D Program

## Global Sea Level Rise From Topex & Jason-1 Compared With Tide Gauge Rates From 1870-1930 and the 20th Century

## Mult-Mission Global Sea Level Rise From RADS

- Global mean sea level based on a simultaneous fit to a single trend and annual function and separate bias estimates for each satellite.

## Global Sea Level Trends From Multiple Altimeters Can We Control the Errors?

- Global Sea Level Trends From Multiple Altimeters *Can We Control the Errors?*

-                      Difference in GSL trends
-                 (Topex+Jason) - (Envisat+ERS2+ERS1)

*Probably a Reference Frame Problem!*

## ALT TideGauge

-  No coherent national or international program at present. Pacific gauge network funded by NOAA/OCO
-  NOAA now funding Gary Mitchum (Univ. South Florida) to produce and run a NOAA operational web-based system

-  Tide gauge calibration only way of determining bias & drift errors.
-  May provide answer to “gappy” record problem.

**Notes:**
1) For the past several years we've been using a set of 64 gauges for the drift estimates, but UH has done a good job in expanding the Fast Delivery set in that time. We have therefore done an extensive evaluation of possible stations to add to the mix. The first panel shows the stations we currently use and the additional ones that we are considering. Note the increased spatial coverage. The final selection has not been done yet, but will be completed in the next few weeks.

##  Argo Profiles of Ocean Heat Content vs. GSLR From Altimetry

-  Argo Profiles of Ocean Heat Content vs. GSLR From Altimetry

- Sea level continued to rise despite cooling and *decrease* in thermosteric sea level

- ~ 6 mm drop in thermosteric sea level

- From *Lyman et al., ****GRL****, 2006*

**Notes:**
The upper ocean cooling reported by Lyman et al. posed problems for closing the global sea level budget, as well as the Earth’s radiation budget at the top of the atmosphere.  By carefully examining the ocean heat content estimates and intercomparison of different types of data, two instrument biases were discovered to be the cause of the apparent cooling.  The first bias was due to a small number of Argo floats.

## Building on Univ. of Colorado site developed by Eric Leuliette -- new LSA hire. 

- Building on Univ. of Colorado site developed by Eric Leuliette -- new LSA hire.
- Multi-satellite based on RADS (Remko Scharroo)
- Monthly Tide Gauge Calibration (Univ. of South Florida with R20 support) -- tied to OCO support of tide gauge network.

## Extending the TOPEX/Jason Global Mean Sea Level Time Series with GEOSAT ObservationsLaury Miller, Remko Scharroo, John Kuhn, Caroline Harbitz

- Extending the TOPEX/Jason Global Mean Sea Level Time Series with GEOSAT ObservationsLaury Miller, Remko Scharroo, John Kuhn, Caroline Harbitz

## Gyre-scale Atmospheric Pressure Variations and their Relationship to 19th and 20th Century Sea Level RiseLaury Miller & Bruce C. Douglas

- Gyre-scale Atmospheric Pressure Variations and their Relationship to 19th and 20th Century Sea Level RiseLaury Miller & Bruce C. Douglas

- Church & White (2006) identified an acceleration in Global Sea Level Rise (GSLR) centered on 1920-1930.

- Here we show that this behavior is closely related to long-term, gyre-scale surface pressure variations similar to the Northern Annular Mode (Arctic Oscillation) and not global mass or volume change.

## Sea level rise is a combination of thermal expansion and additional water from continental sources (e.g. glaciers).

Eric Leuliette has exploited altimetry, in situ measurements of thermosteric changes in sea level, and mass changes inferred from NASA’s GRACE gravity mission in an effort to close the sea level change budget.

- Sea level rise is a combination of thermal expansion and additional water from continental sources (e.g. glaciers).
- Eric Leuliette has exploited altimetry, in situ measurements of thermosteric changes in sea level, and mass changes inferred from NASA’s GRACE gravity mission in an effort to close the sea level change budget.

- Using GRACE to identifying cause(s) of GSRL GRACE(mass) = ALT(mass+vol) - Argo(vol)

## Altimeter Missions

**In orbit**

**Approved**

**Planned****/****Pending Approval**

**97**

**98**

**99**

**00**

**01**

**02**

**03**

**04**

**05**

**06**

**07**

**08**

**09**

**10**

**11**

**12**

**2-f MR & 66-deg, 10-day, 315-km**

**98-deg, 35-day, 80-km ****– failure of on-board recording**

**ERS-2**

**ENVISAT**

**JASON**

** **

**13**

**14**

**15**

** ****Sentinel 3 – 3-sat series**

**Jason **

**108-deg, 17-day, 160-km **

**Jason-3  **

**AltiKa on SARAL**

**TOPEX-Poseidon**

**GEOSAT Follow-on**

**OSTM (Jason-2)**

**HY-2 series**

**SWOT  **

**Timely data access?**

**Notes:**
ERS-2:  The on-board recording no longer functions so observations can only be made available via real-time direct reception, should ESA decide to exercise that option.
GFO:  The oldest, and least accurate, is the U.S. Navy's Geosat-Follow On altimeter launched in 1998.  It had a rocky start, due to the immediate failure of all three of it's GPS receivers which were supposed to provide precise orbits. Satellite laser ranging measurements are being used instead.  GFO just passed it's expected lifetime of 8 years.  It has attitude and battery aging problems, and probably isn't expected to live more than 1 or 2 more years. 
ENVISAT:  Launched in 2002, it has an expected lifetime of 5 years.  It is showing some oscillator drift and power output problems, but presumably will survive until 2007. 
Jason-1:  Launched in 2002, it too has an expected lifetime of 5 years. It's suffering from water vapor radiometer drift and attitude control problems.  One of the four attitude control wheels has already failed and the loss of another is likely to doom the satellite.
OSTM/Jason-2:  On track for launch in 2008.
AltiKa:  While the French Space Agency is likely to approve funding for a piggyback altimeter, the arrangement for flight on an Indian satellite is not yet finalized.  To be successful will require a softening of traditional Indian data restrictions.
Sentinel-3:  This is part of the proposed Sentinel series being pursued by ESA under the GMES Program.  Prospects appear good for the EC funding for the Sentinel series.

## NOAA’s Expanding Role In Satellite Altimetry 

- NOAA’s Expanding Role In Satellite Altimetry

- Jason-2/OSTM --- Launch 2008
- NASA/CNES with NOAA/EUMETSAT junior partners
- NOAA Responsible for ground system -- controlling satellite, downlinking data, near-real time data processing, archive (CLASS) and distribution
- Jason-3 --- Proposed launch 2013
- NOAA & EUMETSAT lead agencies, with CNES and possibly NASA participation.
- Need to secure funding -- NOAA’s share $150M over 5 years?