The UC Davis Semi-Annual Report on Quality Assurance IMPROVE Steering Committee Meeting October 16, 2018 | Fort Collins, Colorado Xiaolu Zhang*, Katrine Gorham, Xiaoya Cheng, Sean Raffuse, Jason Giacomo, Warren White, Nicole Hyslop University of California, Davis Photo Credit: USGS
Introduction UCD has started to deliver semi-annual QA reports since February 2017 (downloadable at http://vista.cira.colostate.edu/ Improve/quality-assurance/) The latest report covers sampling dates from January through December 2017. The primary objectives of the QA report are to: Provide NPS with graphical representations to illustrate key QA parameters for species measured within the network. Highlight observations that may give early indications of emerging trends, whether in atmospheric composition or measurement quality. Serve as a record and tool for ongoing UCD QA efforts.
UCD QA Report Outline Introduction Concentration-Level QC Checks Analytical QC Checks Documentation Site Maintenance Summary Comparisons Across Years Comparisons Between Modules Comparisons Between Collocated Samples Replicate versus Routine Blanks Validation Updates
UCD QA Report Outline Introduction Concentration-Level QC Checks Analytical QC Checks Documentation Site Maintenance Summary Comparisons Across Years Comparisons Between Modules (Filters) Comparisons Between Collocated Samples Replicate versus Routine Blanks Validation Updates
Concentration-Level QC Checks Sulfate 1. Comparisons Across Years 90th Percentile 2011 Multi-year time series plots of 10th, 50th (median) and 90th percentile concentrations for each parameter Six years (2011-2016) data are included to provide context for the 2017 data Useful for examining network- scale trends and analytical consistency 2017 Median 10th Percentile
Decreasing Trend in Nickel (Ni) and Vanadium (V) Concentrations
Higher OC in 2017 summer and fall months Organic Carbon 90th Percentile Median 10th Percentile PM2.5 mass 90th Percentile Median 10th Percentile Higher OC in 2017 summer and fall months Similar trend is seen in PM2.5 mass, EC, fabs, K
Concentration-Level QC Checks 2. Comparisons Between Modules Module B PM2.5 Nylon Module A PTFE Module C Quartz Module D PM10 ions elements mass fabs carbon Sulfur (A) vs. Sulfate (B) Chlorine (A) vs. Chloride (B) fabs (A) vs. EC (C) Reconstructed PM2.5 (A, B, C) vs. Gravimetric PM2.5 (A)
Concentration-Level QC Checks 2. Comparisons Between Modules Module B PM2.5 Nylon Module A PTFE Module C Quartz Module D PM10 ions elements mass fabs carbon Sulfur (A) vs. Sulfate (B) Chlorine (A) vs. Chloride (B) fabs (A) vs. EC (C) Reconstructed PM2.5 (A, B, C) vs. Gravimetric PM2.5 (A)
Concentration-Level QC Checks Reconstructed/Gravimetric PM2.5 mass ratio 75th percentile median 25th percentile 2017 Reconstructed mass = (4.125 × S) + (1.29 × NO3ˉ ) + (1.8 × OC) + (EC) + (2.2 × Al + 2.49 × Si + 1.63 × Ca + 2.42 × Fe + 1.94 × Ti) + (1.8 × chloride)
Concentration-Level QC Checks 3. Comparisons Between Collocated Samples A B C D CL Collocated (A,B,C or D) Routine 𝑆𝑐𝑎𝑙𝑒𝑑 𝑅𝑒𝑙𝑎𝑡𝑖𝑣𝑒 𝐷𝑖𝑓𝑓𝑒𝑟𝑒𝑛𝑐𝑒= collocated − routine / 2 collocated + routine / 2 𝐶𝑜𝑙𝑙𝑜𝑐𝑎𝑡𝑒𝑑 𝑃𝑟𝑒𝑐𝑖𝑠𝑖𝑜𝑛 (𝑐𝑝)= 84𝑡ℎ 𝑝𝑒𝑟𝑐𝑒𝑛𝑡𝑖𝑙𝑒 𝑜𝑓 𝑆𝑅𝐷 −(16𝑡ℎ 𝑝𝑒𝑟𝑐𝑒𝑛𝑡𝑖𝑙𝑒 𝑜𝑓 𝑆𝑅𝐷) 2 𝐹𝑟𝑎𝑐𝑡𝑖𝑜𝑛𝑎𝑙 𝑈𝑛𝑐𝑒𝑟𝑡𝑎𝑖𝑛𝑡𝑦= 100 × 1 𝑛 𝑖=1 𝑛 (𝑐𝑝) 𝑖 2 Fractional uncertainties are calculated from 2013-2016 collocated measurements (Table 1) and will be updated annually.
Collocated SRD plot for XRF elements 𝑆𝑐𝑎𝑙𝑒𝑑 𝑅𝑒𝑙𝑎𝑡𝑖𝑣𝑒 𝐷𝑖𝑓𝑓𝑒𝑟𝑒𝑛𝑐𝑒= collocated − routine / 2 collocated + routine / 2
UCD QA Report Outline Introduction Concentration-Level QC Checks Analytical QC Checks Documentation Site Maintenance Summary Comparisons Across Years Comparisons Between Modules Comparisons Between Collocated Samples Replicate versus Routine Blanks Validation Updates
Analytical QC Checks - Replicates DRI (carbon) and RTI (ion) labs routinely re-analyze ~10% and ~5% of the network samples as replicates, respectively. Replicate analysis are not reported to FED and AQS, but used for QC check. Carbon Fractions Replicate versus Routine Blanks Validation Updates* Massloading, Routine (µg/filter) Massloading, Replicate (µg/filter)
Analytical QC Checks - Blanks Chloride Field Blank lot change Dashed red lines indicate different Nylon filter lots. High Cl- field blanks prior to March 2011 due to improper storage will be discussed in an updated data advisory. Contamination in summer 2017 Chloride Lab Blank
Upcoming Delivery Date UCD QA Report Outline Introduction Concentration-Level QC Checks Analytical QC Checks Documentation Site Maintenance Summary Comparison Across Years Comparisons Between Modules Comparisons Between Collocated Samples Deliverable Upcoming Delivery Date SOPs and TI documents January 31, 2019 Quarterly Site Status Report November 15, 2018 (2018 Q3) February 15, 2019 (2018 Q4) Semiannual Quality Assurance Report (January – June 2018 data) April 30, 2019 Replicate versus Routine Blanks Validation Updates
UCD QA Report Outline Introduction Concentration-Level QC Checks Analytical QC Checks Documentation Site Maintenance Summary Comparison Across Years Comparisons Between Modules Comparisons Between Collocated Samples Summary of Repair Items Sent (Table 3) CSU CIRA Field Audits (Table 4) Summary of UCD Site Visits January through June 2018 (Table 5) Replicate versus Routine Blanks Validation Updates
THANKS!! Looking Forward Continuing effort towards standardizing the report content and figures. XRF analytical QC section will be added in the next report. What else would you like to see in the next QA report? THANKS!!
Extra slides
Sulfate Sulfate (Sulfur) decreases over years
Concentration-Level QC Checks RCMN = (4.125 × S) + (1.29 × NO3ˉ ) + (1.8 × OC) + (EC) + (2.2 × Al + 2.49 × Si + 1.63 × Ca + 2.42 × Fe + 1.94 × Ti) + (1.8 × chloride)
Concentration-Level QC Checks Laser and integrating sphere were replaced on HIPS New calibration (red) consistent with previous one 2. Comparisons Between Modules Light absorption (fabs)/EC ratio
Validation Updates Previous reports Current report: Chloride is used in UCD RCMN formula instead of chlorine to be consistent with CIRA Fractional uncertainties were calculated using 2005-2013 data before 2017 samples; Now are using last 4 years of collocated measurements. BYIS1 (5A module) data are excluded from the fractional uncertainty. Carbon reprocessing and redelivery comparison XRF calibration using multi-elements standards OC and EC artifact calculation change: UCD is now using the same method for carbon blank correction as CIRA; 2017 data are redelivered to reflect the change. New validation tools developed by the UCD software group.
Analytical QC Checks – Replicates y = 0.05+0.98x r2 = 0.992 y = 0.00+1.00x r2 = 1.000 y = 0.10+0.99x r2 = 0.999 Ions (Chloride, Nitrite, Nitrate, Sulfate)
Analytical QC Checks - Blanks OCTR Field Blank Dashed red lines indicate when the DRI Model 2015 analyzers are put to use (2016-1-1) ECTR Field Blank