continuity of improve carbon data through the 1 january 2005 introduction of
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CONTINUITY OF IMPROVE CARBON DATA THROUGH THE 1 JANUARY 2005 INTRODUCTION OF NEW ANALYTICAL INSTRUMENTATION *. - PowerPoint PPT PresentationTRANSCRIPT
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CONTINUITY OF IMPROVE CARBON DATA THROUGH THE 1 JANUARY 2005 INTRODUCTION OF NEW ANALYTICAL INSTRUMENTATION*WHW, 10/2/07 *Chow et al. (2007) JA&WMA 57:1015-1023updated 1/23/08This is an updated and elaborated version of a presentation sent to DRI in August 2007 and presented at the IMPROVE Steering Committee meeting in Durango (http://vista.cira.colostate.edu/improve/Activities/Meetings/2007Pres/C_medians_white.pdf). It applies to carbon data some of the analytical techniques developed at CNL to identify temporal instabilities in XRF data. The plots that follow are snapshots from early stages of a hypothesis-generating exploration, and at this point are intended only for internal discussions of their interpretation.
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We begin with time series of the ratios TOR fraction / total carbon (g/g or mol/mol).VIEWS raw, downloaded 9/07
VIEWS preliminary, downloaded 9/07 (Babs is not included in VIEWS preliminary data, and so was obtained from CNLs internal files.) Scales vary from fraction to fraction, but grid intervals remain constant (as a visual cue to the differences).
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MEDIAN AND INTERQUARTILE RANGE ENTIRE NETWORK, ALL VALID DATA
25th percentile75th percentile
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MEDIAN AND INTERQUARTILE RANGE ENTIRE NETWORK, ALL VALID DATA
2001-2003 NORMAL: for each week {1,2,,52}, the median of 24h medians from that week during 2001-2003
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MEDIAN AND INTERQUARTILE RANGE ENTIRE NETWORK, ALL VALID DATA
unsynchronized sampling during 2/week 1/3day transition: data excludedversion 1 | version 2 samplersIMPROVE IMPROVE_A (DRI/OGC) (DRI Model 2001)
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MEDIAN AND INTERQUARTILE RANGE ENTIRE NETWORK, ALL VALID DATA
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MEDIAN AND INTERQUARTILE RANGE ENTIRE NETWORK, ALL VALID DATA
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MEDIAN AND INTERQUARTILE RANGE ENTIRE NETWORK, ALL VALID DATA
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MEDIAN AND INTERQUARTILE RANGE ENTIRE NETWORK, ALL VALID DATA
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MEDIAN AND INTERQUARTILE RANGE ENTIRE NETWORK, ALL VALID DATA
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MEDIAN AND INTERQUARTILE RANGE ENTIRE NETWORK, ALL VALID DATA
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MEDIAN AND INTERQUARTILE RANGE ENTIRE NETWORK, ALL VALID DATA
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MEDIAN AND INTERQUARTILE RANGE ENTIRE NETWORK, ALL VALID DATA
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MEDIAN AND INTERQUARTILE RANGE ENTIRE NETWORK, ALL VALID DATA
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MEDIAN AND INTERQUARTILE RANGE ENTIRE NETWORK, ALL VALID DATA
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MEDIAN AND INTERQUARTILE RANGE ENTIRE NETWORK, ALL VALID DATA
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Some organic fractions changed abruptly on 1 January 2005.
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Others seemed to anticipate the change in instrumentation.
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The changes in OC and EC are neither abrupt nor dramatic, but the greater regularity of these aggregates makes them noticeable. Winter 2003-4 also appears anomalous.
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We have focused on carbon/carbon ratios up to now. Total organic carbon, OC, can also be compared against non-sulfate hydrogen. This is calculated from the A-module PESA measurement of H and the B-module IC measurement of SO4= on the assumption that all sulfate is ammonium sulfate. On the further assumption that ammonium sulfate accounts for all inorganic hydrogen, non-sulfate hydrogen is referred to as organic hydrogen, OH.Total elemental carbon, EC, can be compared against the A-module HIPS (hybrid integrating plate/sphere) measurement of light absorption. These data are submitted by CNL as LRNC (the NC stands for non-corrected), and delivered by VIEWS as Babs in the non-standard units (108 m)-1. Of course, each measurement added to the comparisons also carries its own errors and uncertainties.
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MEDIAN AND INTERQUARTILE RANGE, ENTIRE NETWORK, ALL VALID DATA
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MEDIAN AND INTERQUARTILE RANGE ENTIRE NETWORK, ALL VALID DATA
The new measurements report less OC, not only relative to TC, but also relative to OH estimated wholly independently. Like OP/TC, OC/OH seemed to anticipate the instrumentation change.
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MEDIAN AND INTERQUARTILE RANGE ENTIRE NETWORK, ALL VALID DATA
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2010 5m2/g
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MEDIAN AND INTERQUARTILE RANGE ENTIRE NETWORK, ALL VALID DATA
Comparison with gravimetric fine mass, considered one of the most reliably accurate of the measurements, gives no clear indication that TC = EC+OC did exhibit any decrease in 2005.