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Within the allied professions of architecture, engineering, and construction, there is an imminent need to creatively hybridize the disparate realms of research, public interest design, and traditional practice. This hybrid has the potential to reinvigorate these professions and shift the relevance of the industry in line with the current and future issues facing the built environment. Snow Kreilich Architects, has begun to combine these disparate realms of practice/inquiry into a hybridized studio model in Minneapolis, Minnesota. This paper will use case study methodology to document and summarize the process of forming such a hybrid. The topics discussed will include: (1) Drawing precedent for research-oriented and purpose-oriented organizations and from the fields of medicine, law, and technology. (2) The underpinnings of hybrid design organizations, drawing precedent from the University of Minnesota's Master of Research Practices in Architecture (MS-RP) program (3) evaluate and discuss the successes and shortcomings associated with hybridizing an existing studio- based architectural practice. (4) Discuss the potential benefits of combining these realms from a financial, operational, and relevance point of view. As a case study, Snow Kreilich Architects' existing architectural practice explored how research within the firm has potential to elevate the everyday work we do and also provide design services through alternative means to marginalized topics and populations, both domestically and abroad. Critically, both types of service are arranged logistically to behave in symbiosis. Within this evolving environment at Snow Kreilich Architects, the unlikely combination of research, architectural services, and public interest design agendas found common ground to be pursued through an innovative business model. Identifying alternative, recurring sources of funding was a critical step in forming an operational and budgetary plan for how research and pro bono activities

A tunable diode laser absorption spectrometer (TDLAS) was operated on the NASA DC‐8 aircraft during the summer INTEX‐NA study to acquire ambient formaldehyde (CH2O) measurements over North America and the North Atlantic Ocean from ∼0.2 km to ∼12.5 km altitude spanning 17 science flights. Measurements of CH2O in the boundary layer and upper troposphere over the southeastern United States were anomalously low compared to studies in other years, and this was attributed to the record low temperatures over this region during the summer of 2004. Formaldehyde is primarily formed over the southeast from isoprene, and isoprene emissions are strongly temperature‐dependent. Despite this effect, the median upper tropospheric (UT) CH2O mixing ratio of 159 pptv from the TDLAS over continental North America is about a factor of 4 times higher than the median UT value of 40 pptv observed over remote regions during TRACE‐P. These observations together with the higher variability observed in this study all point to the fact that continental CH2O levels in the upper troposphere were significantly perturbed during the summer of 2004 relative to more typical background levels in the upper troposphere over more remote regions. The TDLAS measurements discussed in this paper are employed together with box model results in the companion paper by Fried et al. to further examine enhanced CH2O distributions in the upper troposphere due to convection. Measurements of CH2O on the DC‐8 were also acquired by a coil enzyme fluorometric system and compared with measurements from the TDLAS system.

Hydrogen peroxide (H2O2), methyl hydroperoxide (CH3OOH), and formaldehyde (CH2O) were measured over North America and the North Atlantic during the INTEXNA, TOPSE, and SONEX aircraft campaigns. An overview of H2O2, CH3OOH, and CH2O across the geographic and temporal range of these campaigns is presented. H2O2, CH3OOH, and CH2O mixing ratios and variability were larger during INTEX-NA compared to TOPSE and SONEX. Mean H2O2, CH3OOH, and CH2O were 1390, 440, and 480 pptv, respectively, more than two times higher than TOPSE measurements and an order of magnitude higher than SONEX measurements. This is attributed to higher solar radiation levels and the more polluted conditions of INTEX-NA. Mixing ratios and variability decreased with altitude for all three gases and on all three campaigns, except for CH3OOH during TOPSE. The impact of convection on H2O2, CH3OOH, and CH2O is also discussed. Using the ratio H2O2/CH3OOH, convectively influenced air parcels were found to be enhanced in CH3OOH, CH2O, CO, NO, and NO2 while H2O2 and HNO3 were depleted by wet removal. Biomass burning was also shown to increase H2O2, CH3OOH, and CH2O mixing ratios up to 1.5, 2, and 1 ppbv, respectively, even after 4-5 days of transit. Results from this study show considerable variability in H2O2, CH3OOH, and CH2O throughout the North American and North Atlantic troposphere. The variability in the upper troposphere is driven by local photochemical production and transport via regional convection and long-range pathways, suggesting transport mechanisms are important factors to include in photochemical models simulating H2O2, CH3OOH, CH2O, and HOx. Copyright 2007 by the American Geophysical Union.

Ozone (O3) and aerosol scattering ratio profiles were obtained from airborne lidar measurements on thirty‐eight flights over seven deployments covering the latitudes of 40°–85°N between 4 February and 23 May 2000 as part of the Tropospheric Ozone Production about the Spring Equinox (TOPSE) field experiment. Each deployment started from Broomfield, Colorado, with bases in Churchill, Canada, and on most deployments, Thule Air Base, Greenland. Nadir and zenith lidar O3 measurements were combined with in situ O3 measurements to produce vertically continuous O3 profiles from near the surface to above the tropopause. Potential vorticity (PV) distributions along the flight track were obtained from several different meteorological analyses. Ozone, aerosol, and PV distributions were used together to identify the presence of pollution plumes and stratospheric intrusions. Ozone was found to increase in the middle free troposphere (4–6 km) at high latitudes (60°–85°N) by an average of 4.6 ppbv/mo (parts per billion by volume per month) from about 54 ppbv in early February to over 72 ppbv in mid‐May. The average aerosol scattering ratios at 1064 nm in the same region increased rapidly at an average rate of 0.36/mo from about 0.38 to over 1.7. Ozone and aerosol scattering were highly correlated over the entire field experiment, and PV and beryllium (7Be) showed no significant positive trend over the same period. The primary cause of the observed O3 increase in the mid troposphere at high latitudes was determined to be the photochemical production of O3 in pollution plumes with less than 20% of the increase from stratospherically‐derived O3.

During the Tropospheric Ozone Production about the Spring Equinox (TOPSE) aircraft program, ozone depletion events (ODEs) in the high latitude surface layer were investigated using lidar and in situ instruments. Flight legs of 100 km or longer distance were flown 32 times at 30 m altitude over a variety of regions north of 58° between early February and late May 2000. ODEs were found on each flight over the Arctic Ocean but their occurrence was rare at more southern latitudes. However, large area events with depletion to over 2 km altitude in one case were found as far south as Baffin Bay and Hudson Bay and as late as 22 May. There is good evidence that these more southern events did not form in situ but were the result of export of ozone‐depleted air from the surface layer of the Arctic Ocean. Surprisingly, relatively intact transport of ODEs occurred over distances of 900–2000 km and in some cases over rough terrain. Accumulation of constituents in the frozen surface over the dark winter period cannot be a strong prerequisite of ozone depletion since latitudes south of the Arctic Ocean would also experience a long dark period. Some process unique to the Arctic Ocean surface or its coastal regions remains unidentified for the release of ozone‐depleting halogens. There was no correspondence between coarse surface features such as solid ice/snow, open leads, or polynyas with the occurrence of or intensity of ozone depletion over the Arctic or subarctic regions. Depletion events also occurred in the absence of long‐range transport of relatively fresh “pollution” within the high latitude surface layer, at least in spring 2000. Direct measurements of halogen radicals were not made. However, the flights do provide detailed information on the vertical structure of the surface layer and, during the constant 30 m altitude legs, measurements of a variety of constituents including hydroxyl and peroxy radicals. A summary of the behavior of these constituents is made. The measu

The Tropospheric Ozone Production about the Spring Equinox (TOPSE) experiment examined the evolution of tropospheric chemical compositions from February to May 2000 over North America, 40 to 85 N. Hydrogen peroxide (H2O2) and methyl hydroperoxide (CH3OOH) were investigated using instrumental observations aboard the NCAR C-130 research aircraft. Primary TOPSE results indicate both photochemistry and atmospheric dynamics are critical factors controlling the variability of peroxides in this region. From February to May, H2O2 and CH3OOH mixing ratios increased with the greatest relative changes at mid-altitudes. H2O2 ranged from below the detection limit (BDL = 25 pptv) to 380 pptv in winter and from BDL to 1330 pptv during spring. Winter measurements of CH3OOH were from BDL (35 pptv) to 740 pptv with higher levels of BDL to 1400 pptv measured during spring. Peroxides also decreased with latitude at all altitudes. These findings are consistent with those expected from photochemical theory. Evidence also supports a source of CH3OOH to the Arctic from the transport of subtropical air masses. Air mass back trajectories and GOES-derived specific humidity products indicate transport of moist tropical air to the study region coincides with elevated levels of CH3OOH up to 940 pptv. The concurrence of this transport regime with episodic elevated CH3OOH events suggests a source of HOx to the Arctic. However, evidence from this study shows CH3OOH does not greatly contribute to total HOx production which is dominated primarily by reactions of O(lD) and H2O at low latitudes and CH2O at high latitudes.

Tropospheric photochemistry point models are unable to capture the vertical structure of HOx (HO and HO2), important atmospheric oxidants in the troposphere. Specifically, the models underestimate HOx levels in the upper troposphere. Convective vertical motion has been proposed as a mechanism to transport HOx precursors, hydrogen peroxide (H2O2), methylhydroperoxide (CH3OOH), and formaldehyde (CH2O), into the upper troposphere where they are photolyzed to form HOx. Using a convective influence product which incorporated air mass back trajectories and GOES water vapor images, marine tracers methyl iodide and bromoform, and continental tracers tetrachloroethene and dichloromethane where identified as excellent tracers for convective influence in the upper troposphere. Furthermore, the ratio of H2O2 to CH3OOH was shown to detect convection over marine regions due to the preferential removal of H 2O2 by precipitation or reactions with SO2 in cloud droplets. These in-situ convective tracers were used to identify convected air masses throughout the South Pacific. Enhancements up to a factor of 2 were identified in convective outflow during the Northern Hemisphere autumn. However, during the spring, peroxide enhancements were not observed due to excessive wet removal of H2O2 and lower CH3OOH boundary layer mixing ratios. Convective enhancements of CH2O were also not observed. In addition to transport in convective systems in the tropics, subtropical transport with CH3OOH levels up to 1 ppbv were observed in the mid-latitudes. These results show that vertical transport in convective systems is a source of HOx precursors to the upper troposphere and is important in regions where the background troposphere is dry. Furthermore, the impact of convective transport of HOx precursors is not isolated to the tropics, but is important globally.

Low‐ozone (ppbv) air masses were observed in the upper troposphere in northern midlatitudes over the eastern United States and the North Atlantic Ocean on several occasions in October 1997 during the NASA Subsonic Assessment, Ozone and Nitrogen Oxide Experiment (SONEX) mission. Three cases of low‐ozone air masses were shown to have originated in the tropical Pacific marine boundary layer or lower troposphere and advected poleward along a warm conveyor belt during a synoptic‐scale disturbance. The tropopause was elevated in the region with the low‐ozone air mass. Stratospheric intrusions accompanied the disturbances. On the basis of storm track and stratospheric intrusion climatologies, such events appear to be more frequent from September through March than the rest of the year.