Abstract
The Sheppard formula (Q J R Meteorol Soc 82:528–529, 1956) for the dividing streamline height \(H_\mathrm{s}\) assumes a uniform velocity \(U_\infty \) and a constant buoyancy frequency N for the approach flow towards a mountain of height h, and takes the form \(H_\mathrm{s}/h=\left( {1-F} \right) \), where \(F=U_{\infty }/Nh\). We extend this solution to a logarithmic approach-velocity profile with constant N. An analytical solution is obtained for \(H_\mathrm{s}/h\) in terms of Lambert-W functions, which also suggests alternative scaling for \(H_\mathrm{s}/h\). A ‘modified’ logarithmic velocity profile is proposed for stably stratified atmospheric boundary-layer flows. A field experiment designed to observe \(H_\mathrm{s}\) is described, which utilized instrumentation from the spring field campaign of the Mountain Terrain Atmospheric Modeling and Observations (MATERHORN) Program. Multiple releases of smoke at \(F\approx 0.3\)–0.4 support the new formulation, notwithstanding the limited success of experiments due to logistical constraints. No dividing streamline is discerned for \(F\approx 10\), since, if present, it is too close to the foothill. Flow separation and vortex shedding is observed in this case. The proposed modified logarithmic profile is in reasonable agreement with experimental observations.
Similar content being viewed by others
References
Apsley DD, Castro IP (1996) Numerical modeling of flow and dispersion around Cinder Cone Butte. Atmos Environ 31(7):1059–1071
Baines PG (1979a) Observations of stratified flow over two-dimensional obstacles in fluid of finite depth. Tellus 31:351–371
Baines PG (1979b) Observations of stratified flow past three-dimensional barriers. J Geophys Res 84:7834–7838
Baines PG (1987) Upstream blocking and airflow over mountains. Annu Rev Fluid Mech 19(1):75–95
Baines PG (1998) Topographic effects in stratified flows. Cambridge University Press, Cambridge, UK, 500 pp
Baines PG, Smith RB (1993) Upstream stagnation points in stratified flow past obstacles. Dyn Atmos Oceans 18(1–2):105–113
Barenblatt GI (1996) Scaling, self-similarity, and intermediate asymptotics. Cambridge University Press, Cambridge, UK, 386 pp
Batchelor GK (1983) An introduction to fluid dynamics. Cambridge University Press, Cambridge, UK, 615 pp
Beaucage P, Brower MC, Tensen J (2014) Evaluation of four numerical wind flow models for wind resource mapping. Wind Energy 17(2):197–208
Belcher SE, Hunt JCR (1998) Turbulent flow over hills and waves. Annu Rev Fluid Mech 30(1):507–538
Boyer DL, Davies PA (2000) Laboratory studies of orographic effects in rotating and stratified flows. Annu Rev Fluid Mech 32(1):165–202
Brighton PWM (1978) Strongly stratified flow past three-dimensional obstacles. Q J R Meteorol Soc 104:289–307
Carruthers DJ, Hunt JCR (1990) Fluid mechanics of airflow over hills: turbulence, fluxes, and waves in the boundary layer. In: Blumen W (ed) Atmospheric processes in complex terrain. American Meteorological Society, Boston, pp 83–103
Chomaz JM, Bonneton P, Hopfinger EJ (1993) The structure of the near wake of a sphere moving horizontally in a stratified fluid. J Fluid Mech 254:1–21
Chomaz JM, Billant P, Gallaire F (2004) Hydrodynamic instability and transition to turbulence for quasi two-dimensional flows, 2D or not 2D? In: Uijttewaal WSJ, Jirka GH (eds) Shallow flows: research presented at the international symposium on shallow flows. Taylor & Francis Group, London, pp 15–22
Cimorelli AJ, Perry SG, Venkatram A, Weil JC, Paine RJ, Wilson RB, Lee RF, Peters WD, Brode RW (2005) AERMOD: a dispersion model for industrial source applications. Part I: general model formulation and boundary layer characterization. J Appl Meteorol 44(5):682–693
Davis RE (1969) The two-dimensional flow of a stratified fluid over an obstacle. J Fluid Mech 36(1):127–143
Ding L, Calhoun RJ, Street RL (2003) Numerical simulation of strongly stratified flow over a three-dimensional hill. Boundary-Layer Meteorol 107(1):81–11
Doyle JD, Durran DR (2007) Rotor and subrotor dynamics in the lee of three-dimensional terrain. J Atmos Sci 64:4202–4221
Drazin PG (1961) On the steady flow of a fluid of variable density past an obstacle. Tellus 13:239–251
Dyer AJ (1974) A review of flux–profile relationships. Boundary-Layer Meteorol 7:363–372
Fernando JF, Pardyjak ER (2013) Field studies delve into the intricacies of mountain weather. EOS 94(36):313–320
Fernando HJS, Weil JC (2010) Whither the stable boundary layer? A shift in the research agenda. Bull Am Meteorol Soc 91(11):1475–1484
Fernando HJS, Pardyjak ER, Di Sabatino S., Chow FK, De Wekker SFJ, Hoch SW, Hacker J, Pace JC, Pratt T, Pu Z, Steenburgh JW, Whiteman CD, Wang Y, Zajic D, Balsley B, Dimitrova R, Emmitt GD, Higgins CW, Hunt JCR, Knievel JC, Lawrence D, Liu Y, Nadeau DF, Kit E, Blomquist BW, Conry P, Coppersmith RS, Creegan E, Felton M, Grachev A, Gunawardena N, Hang C, Hocut CM, Huynh G, Jeglum ME, Jensen D, Kulandaivelu V, Lehner M, Leo LS, Liberzon D, Massey JD, McEnerney K, Pal S, Price T, Sghiatti M, Silver Z, Thompson M, Zhang H, Zsedrovits T (2015) The MATERHORN—unraveling the intricacies of mountain weather. Bull Am Meteorol Soc. e-View. doi:10.1175/BAMS-D-13-00131.1
Greenslade MD (1994) Strongly stratified airflow over and around mountains. In: Castro IP, Rockliff NJ (eds) Stably stratified flows: flow and dispersion over topography. Oxford University Press, Oxford, pp 25–37
Grubišic V, Doyle JD, Kuettner J, Dirks R, Cohn SA, Pan LL, Mobbs S, Smith RB, Whiteman CD, Czyzyk S, Vosper S, Weissmann M, Haimov S, De Wekker SFJ, Chow FK (2008) The Terrain-Induced Rotor Experiment. Bull Am Meteorol Soc 89(10):1513–1533
Hanazaki H (1989) Drag coefficient and upstream influence in three-dimensional stratified flow of finite depth. Fluid Dyn Res 4(5):317–332
Hunt JCR, Snyder WH (1980) Experiments on stably and neutrally stratified flow over a model three-dimensional hill. J Fluid Mech 96(4):671–704
Jarosz E, Wijesekera HW, Teague WJ, Fribance DB, Moline MA (2014) Observations on stratified flow over a bank at low Froude numbers. J Geophys Res Oceans 119(9):6403–6421
Kaimal JC, Finnigan JJ (1994) Atmospheric boundary layer flows: their structure and measurement. Oxford University Press, New York, 289 pp
Kunkel GJ, Marusic I (2006) Study of the near-wall-turbulent region of the high-Reynolds-number boundary layer using an atmospheric flow. J Fluid Mech 548:375–402
Lee SM, Giori W, Princevac M, Fernando HJS (2006) Implementation of a stable PBL turbulence parameterization for the mesoscale model MM5: nocturnal flow in complex terrain. Boundary-Layer Meteorol 119:109–134
Lin Q, Lindberg WR, Boyer DL, Fernando HJS (1992) Stratified flow past a sphere. J Fluid Mech 240:315–354
Lin Q, Boyer DL, Fernando HJS (1993) Internal waves generated by the turbulent wake of a sphere. Exp Fluids 15(2):147–154
Long RR (1953) Some aspects of the flow of stratified fluids I: a theoretical investigation. Tellus 5:42–58
Long RR (1954) Some aspects of the flow of stratified fluids II: experiments with a two-fluid system. Tellus 6(2):97–115
Long RR (1955) Some aspects of the flow of stratified fluids III: continuous density gradients. Tellus 7(3):341–357
Mahrt L (2014) Stably stratified atmospheric boundary layers. Annu Rev Fluid Mech 46:23–45
Miglietta MM, Rotunno R (2005) Simulations of moist nearly neutral flow over a ridge. J Atmos Sci 62(5):1410–1427
Monti P, Fernando HJS, Princevac M, Chan WC, Kowalewski TA, Pardyjak ER (2002) Observations of flow and turbulence in the nocturnal boundary layer over a slope. J Atmos Sci 59:2513–2534
Politovich MK, Goodrich RK, Morse CS, Yates A, Barron R, Cohn SA (2011) The Juneau terrain-induced turbulence alert system. Bull Am Meteorol Soc 92(3):299–313
Queney P (1948) The problem of airflow over mountains: a summary of theoretical studies. Bull Am Meteorol Soc 29:16–26
Ryan W, Lamb B (1984) Determination of dividing streamline heights and Froude numbers for predicting plume transport in complex terrain. J Air Pollut Control Assoc 34(2):152–155
Ryan W, Lamb B, Robinson E (1984) An atmospheric tracer investigation of transport and diffusion around a large, isolated hill. Atmos Environ 18:2003–2021
Scorer RS (1949) Theory of waves in the lee of mountains. Q J R Meteorol Soc 75(323):41–56
Sheppard PA (1956) Airflow over mountains. Q J R Meteorol Soc 82:528–529
Smith RB (1988) Linear theory of stratified flow past an isolated mountain in isosteric coordinates. J Atmos Sci 45(24):3889–3896
Smith RB (1989) Mountain-induced stagnation points in hydrostatic flow. Tellus A 41(3):270–274
Smith RB (1990) Why can’t stably stratified air rise over high ground. In: Blumen W (ed) Atmospheric processes in complex terrain. American Meteorological Society, Boston, pp 105–107
Smith RB (2002) Stratified flow over topography. In: Grimshaw R (ed) Environmental stratified flows, vol 3. Springer, Berlin, pp 119–159
Smith RB, Grønås S (1993) Stagnation points and bifurcation in 3D mountain airflow. Tellus A 45(1):28–43
Snyder WH, Lawson RE, Thompson RS, Holzworth GC (1980) Observations of flow around Cinder Cone Butte, Idaho. Environmental Protection Agency Report, EPA-600/7-80-150, Research Triangle Park, NC
Snyder WH, Thompson RS, Eskridge RE, Lawson RE, Castro AP, Lee JT, Hunt JCR, Ogawa Y (1985) The structure of strongly stratified flow over hills: dividing-streamline concept. J Fluid Mech 152:249–288
Spangler TC (1987) Comparison of actual dividing-streamline heights to height predictions using the Froude number. J Clim Appl Meteorol 26(1):204–207
Steeneveld GJ, Holtslag AAM, Nappo CJ, Van de Wiel BJH, Mahrt L (2008) Exploring the possible role of small-scale terrain drag on stable boundary layers over land. J Appl Meteorol Climatol 47(10):2518–2530
Streutker DR, Glenn NF (2006) LiDAR measurement of Sagebrush Steppe vegetation heights. Remote Sensing Environ 102(1–2):135–145
Suzuki M, Kuwahara K (1992) Stratified flow past a bell-shaped hill. Fluid Dyn Res 9(1–3):1–18
Tartakovsky D, Broday DM, Stern E (2013) Evaluation of AERMOD and CALPUFF for predicting ambient concentrations of total suspended particulate matter (TSP) emissions from a quarry in complex terrain. Environ Pollut 179:138–145
United States Geological Survey (USGS) (2013) The National Map. Data Retrieved 29 Jul 2013
Vosper SB (2004) Inversion effects on mountain lee waves. Q J R Meteorol Soc 130(600):1723–1748
Vosper SB, Castro IP, Snyder WH, Mobbs SD (1999) Experimental studies of strongly stratified flow past three-dimensional orography. J Fluid Mech 390:223–249
Xu Y, Fernando HJS, Boyer D (1995) Turbulent wakes of stratified flows past a cylinder. Phys Fluids 7(9):2243–2255
Acknowledgments
This research was funded by Office of Naval Research Award # N00014-11-1-0709, Mountain Terrain Atmospheric Modeling and Observations (MATERHORN) Program. The authors wish to thank Brent Fields, Kevin Wilcock and Jeff Wintle (Dugway Proving Ground Explosive Division); without their technical support and expertise, the Materhorn smoke-visualization experiments would have not been possible. In addition, the authors wish to thank Michael Carston and Paul Broderick (Dugway Proving Ground Meteorological Division) for their support and invaluable technical contributions to the set-up and maintenance of the large suite of instruments deployed during the MATERHORN Program. We are also grateful for helpful comments provided by three anonymous reviewers, which led to considerable improvement of the paper.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Leo, L.S., Thompson, M.Y., Di Sabatino, S. et al. Stratified Flow Past a Hill: Dividing Streamline Concept Revisited. Boundary-Layer Meteorol 159, 611–634 (2016). https://doi.org/10.1007/s10546-015-0101-1
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10546-015-0101-1