scientimate.hurricanepressureh80#
Pgrid, Rgrid, RVmax, thetagrid = scientimate.hurricanepressureh80(xgrid, ygrid, xCenter, yCenter, Pc, Vgmax, Rknown, VgRknown, Pn=101325, Rhoa=1.204, \
distCalcMethod='gc', flattendata='no', savedata='no', dispout='no')
Description#
Generate hurricane pressure data on given (x,y) points using method from Holland (1980)
Inputs#
- xgrid
:x (longitude) of points which outputs are calculated at :xgrid can be a single point or 1d or 2d array
- ygrid
:y (latitude) of points which outputs are calculated at :ygrid can be a single point or 1d or 2d array
- xCenter
:x (longitude) of hurricane center (track)
- yCenter
:y (latitude) of hurricane center (track)
- Pc
:Hurricane central surface pressure in (Pa)
- Vgmax
:Maximum hurricane 1-min averaged wind velocity at the gradient level in (m/s) :It can be estimated from Vmax=3.44*(1010-Pc*1e-2)^0.644; where Pc is in (Pa) :and, Vmax is 1-min averaged wind at a 10-m elevation in (m/s) (Atkinson & Holliday, 1977) :Hurricane translation velocity (forward velocity) needs to be removed from Vgmax before applying (e.g. Hu et al., 2012) :Hurricane translation velocity (forward velocity) needs to be added after rotational velocity is calculated
- Rknown
:Radius that hurricane wind velocity is known at that radius in (m) :Rknown should be larger than radius associated to Vmax
- VgRknown
:Hurricane wind velocity at the gradient level which is known at radius Rknown in (m/s)
- Pn=101325
:Ambient surface pressure (external pressure) in (Pa) :Standard atmosphere pressure is 101325 (Pa) :Typical value: Pn=101500 (Pa) for the western North Pacific, Pn= 101000 (Pa) for the North Atlantic :(Batke et al., 2014)
- Rhoa=1.204
:Air density at the gradient level in (kg/m3)
- distCalcMethod=’gc’
:Distance calculation method :’cart’: Distances are calculated on cartesian coordinate :’gc’: Distances are calculated on Great Circle based on Vincenty formula, Vincenty (1975) :Earth radius coonsidered as mean earth radius=6371000 m
- flattendata=’no’
:Define if flat data or not :’no’: does not flat the results, outputs are in 3d array :’yes’: flat the results, outputs are in 2d array
- savedata=’no’
:Define if save data in a file or not in working folder :’no’: does not save, :’yes’: save data as ascii ‘dat’ file, data are flatten regrdless of flattendata value
- dispout=’no’
:Define to display outputs or not :’imagesc’: 2 dimensional plot using imagesc or imshow :’pcolor’: 2 dimensional plot using pcolor :’contour’: 2 dimensional contour plot, number of contour=ncolor :’no’: not display :Use dispout=’no’ if calculation mesh is not 2d array :if there is more than one time step, only the last one is plotted :if flattendata=’yes’ then dispout is set as dispout=’no’
Outputs#
- Pgrid
:Hurricane surface pressure on defined mesh in (Pa)
- Rgrid
:Distance (radius) from hurricane center to each point on the grid
- RVmax
:Distance (radius) from hurricane center to a location of maximum hurricane wind velocity (m)
- thetagrid
:Angle from hurricane center to each point on the grid in (Degree)
Examples#
import scientimate as sm
import numpy as np
import matplotlib.pyplot as plt
#EXAMPLE 1
#Creating calculation mesh
xgrid,ygrid=np.meshgrid(np.linspace(-98,-68,100),np.linspace(16,44,100))
#Longitude of Hurricane Katrine center at max velocity
longCenter=-88.6
#Latitude of Hurricane Katrine center at max velocity
latCenter=26.3
#Hurricane Katrina centeral pressure (Pa) at max velocity
Pc=90200
#Hurricane Katrina translational velocity (m/s) at max velocity
Vt=5.18467
#Hurricane Katrina 1-min sustained maximum velocity (m/s) at max velocity
Vmax=76.5
Vmax=Vmax-Vt #Removing hurricane translation velocity from Vmax
Vgmax=Vmax/0.8 #Converting surface velocity to gradient velocity
#34 kt (17.49 m/s) wind radii maximum extent in northeastern quadrant in (m) for Hurricane Katrina at max velocity
Rknown=370400
VRknown=17.49
VRknown=VRknown-Vt #Removing hurricane translation velocity from VRknown
VgRknown=VRknown/0.8 #Converting surface velocity to gradient velocity
Pn=101325 #Ambient surface pressure (external pressure) in (Pa)
Rhoa=1.204 #Air density in (kg/m3)
Pgrid,Rgrid,RVmax,thetagrid=sm.hurricanepressureh80(xgrid,ygrid,longCenter,latCenter,Pc,Vgmax,Rknown,VgRknown,Pn,Rhoa,\
'gc','no','no','imagesc')
#EXAMPLE 2
#Creating calculation mesh
xgrid,ygrid=np.meshgrid(np.linspace(-98,-68,100),np.linspace(16,44,100))
#Longitude of Hurricane Katrine best track
longtrack=[-75.1,-75.7,-76.2,-76.5,-76.9,-77.7,-78.4,-79.0,-79.6,-80.1,-80.3,-81.3,\
-82.0,-82.6,-83.3,-84.0,-84.7,-85.3,-85.9,-86.7,-87.7,-88.6,-89.2,-89.6,\
-89.6,-89.6,-89.6,-89.6,-89.1,-88.6,-88.0,-87.0,-85.3,-82.9]
#Latitude of Hurricane Katrine best track
lattrack=[23.1,23.4,23.8,24.5,25.4,26.0,26.1,26.2,26.2,26.0,25.9,25.4,\
25.1,24.9,24.6,24.4,24.4,24.5,24.8,25.2,25.7,26.3,27.2,28.2,\
29.3,29.5,30.2,31.1,32.6,34.1,35.6,37.0,38.6,40.1]
#Hurricane Katrina centeral pressure (Pa)
Pc=[100800,100700,100700,100600,100300,100000,99700,99400,98800,98400,98300,98700,\
97900,96800,95900,95000,94200,94800,94100,93000,90900,90200,90500,91300,\
92000,92300,92800,94800,96100,97800,98500,99000,99400,99600]
#Hurricane Katrina translational velocity (m/s)
Vt=np.array([0.00000,3.23091,3.13105,3.86928,4.99513,4.82816,3.27813,2.81998,2.77140,2.53041,\
1.05928,5.30662,3.60661,2.98269,3.61863,3.43691,3.28168,2.85849,3.20404,4.26279,\
5.31340,5.18467,5.39195,5.46121,5.66270,1.02958,3.60354,4.63312,8.02540,8.01558,\
8.12721,8.31580,10.75406,12.28350])
#Hurricane Katrina 1-min sustained maximum velocity (m/s)
Vmax=np.array([15.3,15.3,15.3,17.850,20.4,22.950,25.5,28.050,30.6,35.7,35.7,33.150,\
38.250,43.350,45.9,48.450,51.0,51.0,51.0,63.750,73.950,76.5,71.4,63.750,\
56.1,56.1,53.550,40.8,25.5,20.4,15.3,15.3,15.3,12.750])
Vmax=Vmax-Vt #Removing hurricane translation velocity from Vmax
Vgmax=Vmax/0.8 #Converting surface velocity to gradient velocity
#34 kt (17.49 m/s) wind radii maximum extent in northeastern quadrant in (m) for Hurricane Katrina
RknownRaw=[0,0,0,111120,111120,111120,111120,111120,129640,np.nan,129640,138900,\
138900,138900,166680,240760,240760,259280,259280,296320,333360,370400,370400,370400,\
np.nan,370400,np.nan,185200,138900,138900,0,0,0,0]
#34 kt (17.49 m/s) wind radii maximum extent in northeastern quadrant in (m) for Hurricane Katrina
Rknown=[0,0,0,111120,111120,111120,111120,111120,129640,129640,129640,138900,\
138900,138900,166680,240760,240760,259280,259280,296320,333360,370400,370400,370400,\
370400,370400,277800,185200,138900,138900,0,0,0,0]
VRknown=np.ones(34)*17.49
VRknown=VRknown-Vt #Removing hurricane translation velocity from VRknown
VgRknown=VRknown/0.8 #Converting surface velocity to gradient velocity
Pn=101325 #Ambient surface pressure (external pressure) in (Pa)
Rhoa=1.204 #Air density in (kg/m3)
Pgrid,Rgrid,RVmax,thetagrid=sm.hurricanepressureh80(xgrid,ygrid,longtrack[3:27],lattrack[3:27],Pc[3:27],Vgmax[3:27],Rknown[3:27],VgRknown[3:27],Pn,Rhoa,\
'gc','no','no','imagesc')
#EXAMPLE 3
xgrid=np.linspace(0,10,100) #(Degree)
ygrid=np.ones(100)*20 #(Degree)
longCenter=0 #(Degree)
latCenter=20 #(Degree)
Pc=90200 #(Pa)
Vt=5.18467 #(m/s)
Vmax=76.5 #(m/s)
Vmax=Vmax-Vt
Vgmax=Vmax/0.8 #(m/s)
Rknown=370400 #(m)
VRknown=17.49 #(m/s)
VRknown=VRknown-Vt
VgRknown=VRknown/0.8 #(m/s)
Pn=101325 #Ambient surface pressure (external pressure) in (Pa)
Rhoa=1.204 #Air density in (kg/m3)
Pgrid,Rgrid,RVmax,thetagrid=sm.hurricanepressureh80(xgrid,ygrid,longCenter,latCenter,Pc,Vgmax,Rknown,VgRknown,Pn,Rhoa,\
'gc','no','no','no')
plt.plot(Rgrid,Pgrid)
References#
Data
www.nhc.noaa.gov/data/
www.nhc.noaa.gov/data/hurdat/hurdat2-format-nencpac.pdf
coast.noaa.gov/hurricanes
www.aoml.noaa.gov/hrd/data_sub/re_anal.html
Atkinson, G. D., & Holliday, C. R. (1977). Tropical cyclone minimum sea level pressure/maximum sustained wind relationship for the western north Pacific. Monthly Weather Review, 105(4), 421-427.
Batke, S. P., Jocque, M., & Kelly, D. L. (2014). Modelling hurricane exposure and wind speed on a mesoclimate scale: a case study from Cusuco NP, Honduras. PloS one, 9(3), e91306.
Holland, G. J. (1980). An analytic model of the wind and pressure profiles in hurricanes. Monthly weather review, 108(8), 1212-1218.
Holland, G. (2008). A revised hurricane pressure–wind model. Monthly Weather Review, 136(9), 3432-3445.
Holland, G. J., Belanger, J. I., & Fritz, A. (2010). A revised model for radial profiles of hurricane winds. Monthly Weather Review, 138(12), 4393-4401.
Phadke, A. C., Martino, C. D., Cheung, K. F., & Houston, S. H. (2003). Modeling of tropical cyclone winds and waves for emergency management. Ocean Engineering, 30(4), 553-578.