1. In Situ Airborne Formaldehyde (ISAF)
Thomas F. Hanisco (NASA GSFC)
Glenn Wofe (NASA JCET)
Jason St. Clair (NASA JCET)
Daniel Anderson (U Md)
ATom Science Team Meeting
22-24, July, 2015

4. HCHO regional/seasonal profiles

5. CONTRAST (Guam Jan/Feb 2014) Atom-like

6. Modeled and Measured HCHO during descent near Manus
UWCM Box Model Results
Modeled and Measured HCHO during descent near Manus
Model underpredicts HCHO at pressures greater than 700 hPa.
Model predicts methane chemistry dominates at all levels. Isoprene and it’s oxidation products not important.

7. SH HCHO underpredicted. Something interesting here?
G. Zeng, et al, Atmos. Chem. Phys., 2015

8. In situ airborne formaldehyde (ISAF)
Size: 43 x 38 x 60 cm
Weight: 25 kg
Power: VDC
The configuration for the GV includes a pump (300 W 10 kg) and control interface box (5 kg).

9. Measuring Formaldehyde
The laser is continuously tuned between a large formaldehyde rotational transition and a non-resonant wavelength.
Dl = nm
The concentration of formaldehyde is proportional to the difference between the online and the offline signals.
Detection Limit = 20 pptv/s
Accuracy: +/- 10%
Zero uncertainty: +/- 20 pptv
Data rate 10 Hz
Fluorescence = Online(Fluorescence + Rayleigh + Raman) – Offline(Rayleigh + Raman)
Maria Cazorla, et al., Atmos. Meas. Tech.,  8(2), (2015).

10. Team members Steve Bailey, Jason St. Clair, Andrew Swanson Glenn Wolfe
Heather Arkinson (U Md)