TY - JOUR

T1 - NOx and O3 above a tropical rainforest

T2 - an analysis with a global and box model

AU - Pike, R. C.

AU - Lee, J. D.

AU - Young, P. J.

AU - Carver, G. D.

AU - Yang, X.

AU - Warwick, N.

AU - Moller, S.

AU - Misztal, P.

AU - Langford, Ben

AU - Stewart, D.

AU - Reeves, C. E.

AU - Hewitt, C. N.

AU - Pyle, J. A.

N1 - © Author(s) 2010. This work is distributed under the Creative Commons Attribution 3.0 License.

PY - 2010

Y1 - 2010

N2 - A cross-platform field campaign, OP3, was conducted in the state of Sabah in Malaysian Borneo between April and July of 2008. Among the suite of observations recorded, the campaign included measurements of NOx and O3 – crucial outputs of any model chemistry mechanism. We describe the measurements of these species made from both the ground site and aircraft. We then use the output from two resolutions of the chemistry transport model p-TOMCAT to illustrate the ability of a global model chemical mechanism to capture the chemistry at the rainforest site. The basic model performance is good for NOx and poor for ozone. A box model containing the same chemical mechanism is used to explore the results of the global model in more depth and make comparisons between the two. Without some parameterization of the nighttime boundary layer – free troposphere mixing (i.e. the use of a dilution parameter), the box model does not reproduce the observations, pointing to the importance of adequately representing physical processes for comparisons with surface measurements. We conclude with a discussion of box model budget calculations of chemical reaction fluxes, deposition and mixing, and compare these results to output from p-TOMCAT. These show the same chemical mechanism behaves similarly in both models, but that emissions and advection play particularly strong roles in influencing the comparison to surface measurements.

AB - A cross-platform field campaign, OP3, was conducted in the state of Sabah in Malaysian Borneo between April and July of 2008. Among the suite of observations recorded, the campaign included measurements of NOx and O3 – crucial outputs of any model chemistry mechanism. We describe the measurements of these species made from both the ground site and aircraft. We then use the output from two resolutions of the chemistry transport model p-TOMCAT to illustrate the ability of a global model chemical mechanism to capture the chemistry at the rainforest site. The basic model performance is good for NOx and poor for ozone. A box model containing the same chemical mechanism is used to explore the results of the global model in more depth and make comparisons between the two. Without some parameterization of the nighttime boundary layer – free troposphere mixing (i.e. the use of a dilution parameter), the box model does not reproduce the observations, pointing to the importance of adequately representing physical processes for comparisons with surface measurements. We conclude with a discussion of box model budget calculations of chemical reaction fluxes, deposition and mixing, and compare these results to output from p-TOMCAT. These show the same chemical mechanism behaves similarly in both models, but that emissions and advection play particularly strong roles in influencing the comparison to surface measurements.

KW - VOLATILE ORGANIC-COMPOUNDS

KW - REACTION MASS-SPECTROMETRY

KW - NITROGEN-OXIDES

KW - BOUNDARY-LAYER

KW - TROPOSPHERIC OZONE

KW - ATMOSPHERIC CHEMISTRY

KW - 3-DIMENSIONAL MODEL

KW - DRY DEPOSITION

KW - TRACE GASES

KW - RURAL SITE

U2 - 10.5194/acp-10-10607-2010

DO - 10.5194/acp-10-10607-2010

M3 - Journal article

VL - 10

SP - 10607

EP - 10620

JO - Atmospheric Chemistry and Physics

JF - Atmospheric Chemistry and Physics

SN - 1680-7316

IS - 21

ER -