Ensuring the Climate Record from the NPOESS and GOES-R Spacecraft Elements of a Strategy to Recover Measurement Capabilities Lost in Program Restructuring (2008) / Chapter Skim
Currently Skimming:
3 Recommended Short-Term Recovery Strategy
3 Recommended Short-Term Recovery Strategy
Pages 29-67
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 29... ...
RATIONALE FOR PRIORITIZATION: NPOESS LOST CAPABILITIES Microwave Radiometry Related NPOESS Sensor CMIS Post-Nunn-McCurdy "A reduced capability sensor" Status CMIS canceled; descoped MIS instrument to be included on C2 and later platforms Climate Applications Sea-surface temperature and wind, sea ice extent, snow cover, soil wetness, atmospheric moisture Mitigation Priority Tier 1 The process by which the committee performed its prioritization is discussed in Chapter 2; the priorities are based on an average of each member's numerical ranking of the importance of the lost or degraded climate capability, according to an unweighted average of responses to the nine questions shown in Chapter 2. See especially the report of the June 2007 workshop (NRC, 2008; reprinted in Appendix B)
|
From page 30... ...
MW surface measurements include sea-surface temperature and wind, sea ice extent, snow cover, and soil wetness. The higher frequencies provide information on atmospheric moisture in all of its various forms: vapor, cloud, rain, and ice.
|
From page 31... ...
with those of the advanced ocean vector winds scatterometer mission, known as the Extended Ocean Vector Winds Mission (XOVWM) , which was recommended in the 2007 NRC Earth Science and Applications from Space decadal survey. XOVWM's ability to provide highly accurate wind vectors at a high spatial resolution (5 km)
|
From page 32... ...
However, the SSM/IS lacks both the spatial resolution and spectral range required for adequate climate monitoring. Should AMSR-2 be delayed or experience an early failure, a significant data gap of many years will occur.
|
From page 33... ...
. Preferred Recovery Strategy and Other Mitigation Options The preferred mitigation is to build a new MW radiometer specifically designed for climate monitoring, and fly it on either a free flyer or a flight of opportunity.
|
From page 34... ...
recommended in the 2007 NRC decadal survey Earth Science and Applications from Space. Radar Altimetry Related NPOESS Sensor ALT Post-Nunn-McCurdy Status "A demanifested sensor" Climate Applications Sea level height, regional ocean currents, basin-scale ocean circulation Mitigation Priority Tier 1 Highlights of Analysis Sea level is a fundamental indicator of changes in Earth's climate.
|
From page 35... ...
a gap in the record will make it more difficult to determine if the rate of sea level rise is accelerating -- ultimately requiring an even longer time series before this determination can be made. Sea level measurements from satellite altimetry benefit a broad array of climate science disciplines including ocean science, cryospheric science, hydrology, and climate modeling applications because sea level change is a barometer for changes in the global water cycle.
|
From page 36... ...
. The predictions of future sea level change were one of the most contentious aspects of the IPCC 4th assessment and thus satellite altimetry will be an important tool for scientists preparing future assessments.
|
From page 37... ...
For these reasons, the originally intended NPOESS altimetry capability was undesirable for climate studies. In summary, the committee recognizes the importance of an uninterrupted record of sea level change measurements for climate science research and policy making, and thus strongly advocates that the record of sea level change from these missions be continued.
|
From page 38... ...
The agencies' long-term plan should include a series of precision altimetry free flyers in non-Sun-synchronous orbit designed to provide for climate-quality measurements of sea level. Earth Radiation Budget Related NPOESS Sensor ERBS Post-Nunn-McCurdy Status "A demanifested sensor" Climate Applications Earth radiation budget at the top and bottom of the atmosphere Mitigation Priority Tier 1 Highlights of Analysis Measurements of regional and global radiation balance date to the 1960s when the first satellites were launched, and they were further enabled with the launch in the late 1970s of Nimbus 6 and 7, which carried the first true broadband radiation scanning sensors.
|
From page 40... ...
Thus, TOA radiation measurements must be overlapping from one mission to the next; a gap of any length will restart the climate record at zero. Earth radiation budget measurements have played an important role in climate prediction and projections.
|
From page 41... ...
surface air temperature and (b) cloud radiative forcing between 2000 and 2080 for IPCC AR4 GCM simulations (5-year running means)
|
From page 42... ...
Recommendation: To minimize the risk of a potential data gap, the committee reiterates the recommendation of the 2007 Earth Science and Applications from Space decadal survey to manifest the CERES FM-5 on NPP.21 The agencies should further develop an ERB instrument series and provide for subsequent flights on Sun-synchronous platforms to continue the Earth radiation budget long-term record. Hyperspectral Diurnal Coverage Related NPOESS Sensor CrIS/ATMS Post-Nunn-McCurdy Status "A reduced coverage sensor" Climate Applications Vertical temperature and moisture profiles, outgoing longwave radiation, greenhouse gas amounts, cloud properties, precipitation Mitigation Priority Tier 2 Highlights of Analysis Understanding the diurnal variation of climate-relevant parameters and processes is essential for the improvement of the underlying physics of climate models, which must sufficiently capture the physics of short-time-scale processes to enable accurate predictions over long time periods.22 Greater sampling of the diurnal variability of 19 The committee was informed NPP could launch no earlier than 14 months after delivery of the final instrument.
|
From page 43... ...
Model 0.1 0.0 −0.1 −0.2 0 5 10 15 20 Local Hour, T FIGURE 3.6 Diurnal cycle of sea surface temperature.
|
From page 44... ...
Recommendation: The CrIS/ATMS instrument suite should be restored to the 05:30 NPOESS orbit to provide improved hyperspectral diurnal coverage and support atmospheric moisture and temperature vertical profile key performance parameters. Solar Irradiance Related NPOESS Sensor TSIS Post-Nunn-McCurdy Status "A demanifested sensor" Climate Applications Total solar irradiance, spectral solar irradiance Mitigation Priority Tier 2 Post-Nunn-McCurdy, soundings are limited to the 01:30 NPOESS C1 orbit and 09:30 MetOp orbit.
|
From page 45... ...
The current record of total solar irradiance extends uninterrupted since 1978 (Figure 3.7) and, although one of the longest continuous space-based climate records, covers less than three solar activity cycles.
|
From page 46... ...
As Earth's only true external forcing, and with known variations arising from the Sun's activity, inadequate knowledge of future solar forcing guarantees ambiguity in climate change attribution. The value of a reliable, uninterrupted record of solar irradiance extends well beyond the most visible and obvious applications of climate change simulations and policy making regarding global warming.
|
From page 47... ...
. They suggest that climate response to solar irradiance forcing involves dynamical motions within the atmosphere in addition to thermal processes.
|
From page 48... ...
Ironically, demanifesting TSIS from NPOESS terminates the solar irradiance record even as recognition of the potentially pervasive and subtle nature of climate responses to solar forcing is growing. Without TSIS on NPOESS, the total solar irradiance record will terminate after the flight of the total irradiance monitor (TIM)
|
From page 49... ...
Of the two, total solar irradiance is a more mature, less complex, and less costly measurement. Further, it has a longer current climate data record at risk than spectral irradiance.
|
From page 50... ...
Aerosol Properties Related NPOESS Sensor APS Post-Nunn-McCurdy Status "A demanifested sensor" Climate Applications Aerosol properties Mitigation Priority Tier 3 Highlights of Analysis Quantifying the effects of aerosols on the climate system remains a significant challenge. Among the most important aspects of this challenge is the need to globally monitor aerosol properties sufficiently well to determine aerosol climate forcing, which in turn requires knowledge of aerosol composition and size, and optical properties such as optical depth and particle absorption over a sufficiently broad spectral range.
|
From page 51... ...
The only increase in natural forcing of any significance between 1750 and 2005 occurred in solar irradiance. Positive forcings lead to warming of climate and negative forcings lead to a cooling.
|
From page 52... ...
• NASA and NOAA should continue to mature aerosol remote sensing technology and plan for the development of operational instruments for accommodation on future platforms and/or flights of opportunity. Ocean Color Related NPOESS Sensor VIIRS Post-Nunn-McCurdy Status "A reduced coverage sensor" Performance degradation is also expected Climate Applications Aerosols, ocean color Mitigation Priority Tier 3 Highlights of Analysis Monitoring of variability and change in the ocean ecosystems is a key part of a comprehensive climate o bserving system -- understanding the spatial and temporal changes in ocean biology is a critical component of the Earth system and is fundamental to diagnosing the interaction between the physical climate system and biogeo chemical cycles.
|
From page 53... ...
It is important to recognize that the remaining 13:30 orbit, while well suited for these measurements, was not intended to provide the sole measurement vantage point for ocean color because of the deleterious effects of sun glint over portions of the oceans caused by near-specular bright sun reflections masking ocean color signals as shown in Figure 3.12. 33 Unfortunately, in addition to the reduced coverage caused by the elimination of the 09:30 NPOESS orbit, the NPP VIIRS sensor has developmental manufacturing anomalies associated with spectral bands particularly critical to both aerosol and ocean color measurements (Box 3.2)
|
From page 54... ...
Research points to the need to resolve diurnal time scales in ocean temperature and air-sea heat exchanges because nonlinearities in the atmosphere, in the ocean, and in the coupled system lead to rectification of the fast time scales and because daily coupling of the ocean and atmosphere in coupled models is one source of the errors found in results from these models. Clearly, the threat to ocean ecosystems is significant, and establishing a climate record of the ecosystem via ocean color has merit.
|
From page 55... ...
? Impact of optical crosstalk to Ocean Color EDRs by two problematic filter arrays," Fourth Visible/ 3.2.1.eps fixed image Infrared Imager/Radiometer Suite (VIIRS)
|
From page 56... ...
, and use by IPCC and CCSP (question 7) .36 Preferred Recovery Strategy and Other Mitigation Options The IPO and VIIRS team should continue to make all practical efforts to improve VIIRS performance to meet specifications and avoid the anticipated degradation in accuracy.
|
From page 57... ...
The agencies should also work with international partners to ensure community access to ocean color and ancillary calibration/validation data from international platforms during the gap likely to be experienced prior to launch of C1. Ozone Profiles Related NPOESS Sensor OMPS-Limb Post-Nunn-McCurdy Status "A demanifested sensor" Now restored to NPP Climate Applications Ozone profiles Mitigation Priority Tier 3 Ozone profile measurements are needed to both monitor the ozone recovery process and understand the impacts of climate change on ozone layer recovery.
|
From page 58... ...
The agencies should consider the relative cost/benefit of reintegration of OMPS-Limb capabilities for NPOESS platforms carrying OMPS-Nadir based on the degree of integration inherent in the instrument's original design. RATIONALE FOR PRIORITIZATION: GOES-R LOST CAPABILITIES Geostationary Advanced Hyperspectral Sounding Related GOES-R Sensor HES Current Status "A demanifested sensor" Climate Applications High temporal resolution temperature and moisture profiles for process studies Mitigation Priority Tier 2 Geostationary sounders provide the capability of observing diurnal variation of climate variables including cloudiness, surface (sea and land)
|
From page 59... ...
On decade to century time scales, the impact of increased water vapor is realized through alterations in large-scale cloud distribution, which reflect both the water-vapor distribution and the hydrologic cycle's response. Also, the latent heating of clouds and its radiative effects influence the large-scale atmospheric circulation and hydrologic cycle -- additional complexities that need to be better understood.
|
From page 60... ...
Hyperspectral infrared measurements from GEO would continuously describe the clear-sky vertical moisture structure, more than double the temperature profile information content from today's sounders, and permit new wind profiling capabilities by constantly tracking retrieved water vapor profile features at many discrete levels. Assimilated into the next generation of numerical weather prediction models and used for "nowcasts," observations from the GEO advanced sounder could enable improved analyses of severe weather and hurricanes, with the potential to save lives while also providing important
|
From page 61... ...
. Preferred Recovery Strategy and Other Mitigation Options The preferred strategy for the recovery of advanced geostationary hyperspectral sounding is consistent with the decadal survey, NOAA's Analysis of Alternatives, and community letters: an earliest possible flight of a demonstration mission in GEO orbit, followed by the earliest possible provision of sustained and robust operational GEO hyperspectral sounder series -- beginning no later than GOES-T.
|
From page 62... ...
With the cancellation of HES, coastal waters imagery capabilities in the GOES-R time frame were essentially lost. While the primary benefit of geostationary coastal waters imagery is to coastal monitoring, management, and remediation,50 there are important secondary benefits related to regional climate response that would be difficult to assess by any other means.51 These benefits are primarily associated with the higher temporal resolution afforded by use of a geostationary orbit, and higher spatial resolution intended for the CWI.
|
From page 63... ...
This is perhaps unsurprising, as coastal waters imagery is primarily intended to serve other, non-climate applications and research needs. Preferred Recovery Strategy and Other Mitigation Options Provision for coastal waters imaging should be considered by the agencies based on non-climate applications.
|
From page 64... ...
The agencies' long-term plan should include a series of precision altimetry free flyers in non-Sun-synchronous orbit designed to provide for climate-quality measurements of sea level. Earth Radiation Budget To minimize the risk of a potential data gap, the committee reiterates the recommendation of the 2007 Earth Science and Applications from Space decadal survey to manifest the CERES FM-5 on NPP.
|
From page 65... ...
2004. Present-day sea level change: Observations and causes.
|
From page 66... ...
2001. Recent mass balance of polar ice sheets inferred from patterns of global sea level change.
|
From page 67... ...
2003. Secular total solar irradiance trend during solar cycles 21–23.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.