Considerations for the Long-Term Atmospheric Observing Network

Transcription

1 Considerations for the Long-Term Atmospheric Observing Network 1. Land Cover / Land Use & Change 2. Spatial & temporal scale of climate anomalies 3. Climatological wind patterns 4. Expected signals vs. natural variability (noise) aircraft, towers 5. Independent confirmation of fluxes? 6. Logistics this is a Long Term network! viewgraphs at ftp://ftp.cmdl.noaa.gov/pub/peter/nacpsept2001/

2 M4973.M P (Color Comp)

3 M4964.M P (Color Comp)

4 M4971.M P (Color Comp)

5 M4986.M P (Color Comp)

6 Conterminous USA + Hawaii, Puerto Rico & US Virgin Islands million acres ( = million square km) Rangeland Forest Pasture CRP* Cropland Other Developed Federal Source: USDA Natural Resources Conservation Service (*CRP = Conservation Reserve Program)

7 M5150.M P (Color Comp)

8 M5096.M P (Color Comp)

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11 8 4 Wisconsin Tower 396 m AGL North Carolina Tower 496 m AGL Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan

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17 Aircraft Data Detrended Function Fit Carr, Colorado 2km 3km 4km 5km 6km 7km 8km CO2 (ppm) Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Year = 1997

18 Park Falls Wisconsin Tower Variance of Daily Mean Data Heigth AGL (m) Residiual Std Dev from Smooth Curve (ppm)

19 Carr Colorado Aircraft Data (ground level is 1740 m ASL) Height ASL (km) Residual Std Dev from Smooth Curve (ppm)

20 Components of a long-term observing station 1. Aircraft vertical profiles 0-6 km every 2 days (good weather) in-situ analyzer, flasks every 10 days 2. Tall tower m continuous, all weather 3. AmeriFlux tower 0-30 m continuous (fluxes in good weather only) 4. FTIR column integral full column continuous (good weather only) multiple species (CO 2, CH 4, CO, N 2 O, etc.) development work needed!

21 Advantages & Disadvantages of Flask Sampling Advantages: Multiple species & isotopes (CO 2, CH 4, CO, H 2, N 2 O, SF 6, d 13 C, d 18 O) Consistent analysis (one analyzer, one set of working standards) Disadvantages: Low spatial resolution Shipping/logistics Storage issues

22 (a) a, 13:25-13:55 UT descent ascent CMDL flask tower up to 410ppm

23 COBRA-2000 Campaign for < 7km: mean(sd) = 0.21(0.44), n = CMDL Flasks - Harvard in-situ CO2 (ppm) Altitude (km ASL)

24 major cities AmeriFlux sites FM Towers TV Towers CCG flasks CCG aircraft

25 Attributes of a Continuous CO 2 Analyzer for Aircraft Network Sampling 1. Fully automated 2. Low maintenance 2. Low flow rate low reference gas use 4. Stable signal (pressure, temperature, motion)

26 Long-Term Sites Phase 1, Summer 2004 major cities AmeriFlux sites FM Towers TV Towers CCG + AES flasks CCG aircraft NEW aircraft

27 Long-Term Sites Phase 3, Summer 2005 & Beyond other new aircraft sites: Barrow, AK Sitka, AK Yellowknife, NWT St. Anthony, NFL major cities AmeriFlux sites FM Towers TV Towers CCG + AES flasks CCG aircraft NEW aircraft

28 (b) c, 21:24-21:44 UT descent ascent CMDL flask tower

29 (c) a, 13:24-13:51 UT descent ascent CMDL flask tower up to 399ppm

30 (d) b, 17:59-18:21 UT descent ascent CMDL flask tower

31 (e) c, 21:24-21:42 UT descent ascent CMDL flask tower