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/
M4973.M P (Color Comp)
M4964.M P (Color Comp)
M4971.M P (Color Comp)
M4986.M P (Color Comp)
Conterminous USA + Hawaii, Puerto Rico & US Virgin Islands 1894.2 million acres ( = 7.665 million square km) Rangeland 406.0 407.0 Forest Pasture 120.0 CRP* Cropland 32.7 377.0 402.1 51.1 98.3 Other Developed Federal Source: USDA Natural Resources Conservation Service (*CRP = Conservation Reserve Program)
M5150.M P (Color Comp)
M5096.M P (Color Comp)
8 4 Wisconsin Tower 396 m AGL 1995-2001 0-4 -8-12 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 4 0 North Carolina Tower 496 m AGL 1992-1999 -4-8 -12 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan
5 4 3 2 Aircraft Data Detrended Function Fit Carr, Colorado 2km 3km 4km 5km 6km 7km 8km CO2 (ppm) 1 0-1 -2-3 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Year = 1997
Park Falls Wisconsin Tower Variance of Daily Mean Data 1994-2001 396 Heigth AGL (m) 244 122 76 30 11 3 4 5 6 7 8 Residiual Std Dev from Smooth Curve (ppm)
Carr Colorado Aircraft Data 1992-2001 (ground level is 1740 m ASL) 8 7 6 Height ASL (km) 5 4 3 2 0.8 1.0 1.2 1.4 1.6 1.8 Residual Std Dev from Smooth Curve (ppm)
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 0-600 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!
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
25 30 35 40 45 5 4 (a) 000823a, 13:25-13:55 UT descent ascent CMDL flask tower 3 2 1 up to 410ppm 0 0 3 6 9 12 15 351 354 357 360 363 366
COBRA-2000 Campaign for < 7km: mean(sd) = 0.21(0.44), n = 126 3 CMDL Flasks - Harvard in-situ CO2 (ppm) 2 1 0-1 0 1 2 3 4 5 6 7 8 9 10 Altitude (km ASL)
major cities AmeriFlux sites FM Towers TV Towers CCG flasks CCG aircraft
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)
Long-Term Sites Phase 1, Summer 2004 major cities AmeriFlux sites FM Towers TV Towers CCG + AES flasks CCG aircraft NEW aircraft
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
25 30 35 40 45 5 4 (b) 000823c, 21:24-21:44 UT descent ascent CMDL flask tower 3 2 1 0 0 3 6 9 12 15 351 354 357 360 363 366
25 30 35 40 45 5 4 (c) 000824a, 13:24-13:51 UT descent ascent CMDL flask tower 3 2 1 up to 399ppm 0 0 3 6 9 12 15 351 354 357 360 363 366
25 30 35 40 45 5 4 (d) 000824b, 17:59-18:21 UT descent ascent CMDL flask tower 3 2 1 0 0 3 6 9 12 15 351 354 357 360 363 366
25 30 35 40 45 5 4 (e) 000824c, 21:24-21:42 UT descent ascent CMDL flask tower 3 2 1 0 0 3 6 9 12 15 351 354 357 360 363 366