Exemple #1
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def thetal(press, Temp, rt):
    """
    input: press in kPa  (1d vector or scalar)
           temp in K  (1d vector or scalar
           mixing ratio in kg/kg  (1d vector or scalar)
    # emanuel p. 121  4.5.15
    """
    isscalar = test_scalar(press, Temp, rt)
    press = np.atleast_1d(press)
    Temp = np.atleast_1d(Temp)
    rt = np.atleast_1d(rt)
    rl = np.empty_like(rt)
    rsat = rs_tp(Temp, press)
    CPn = tc.RD + rt * tc.RV
    chi = CPn / (tc.CPD + rt * tc.CPV)
    gamma = (rt * tc.RV) / CPn
    saturated = rt > rsat
    rl[saturated] = rt[saturated] - rsat[saturated]
    unsaturated = np.logical_not(saturated)
    rl[unsaturated] = 0
    LV = L_t(Temp)
    theta = Temp * (tc.P0 / press)**chi
    term1 = (1. - rl / (tc.EPS + rt))**chi
    term2 = (1 - rl / rt)**(-gamma)
    term3 = -LV * rl / (CPn * Temp)
    term3 = np.exp(term3)
    theThetal = theta * term1 * term2 * term3
    if isscalar:
        theThetal = theThetal[0]
    return theThetal
Exemple #2
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def tro_trtp(t, rt, pressKpa):
    """in: t=temperature (K),pressKpa= pressure (kPa)
           rt=mixing ratio (kg/kg)
       out:tro=density temperature (K)  (vector)
    """
    isscalar = test_scalar(t, rt, pressKpa)
    if not isscalar:
        t = np.atleast_1d(t)
        rt = np.atleast_1d(rt)
        rv = np.empty_like(rt)
        pressKpa = np.atleast_1d(pressKpa)
    rs = rs_tp(t, pressKpa)
    out = np.empty(rs.shape, dtype=np.float)
    saturated = (rt >= rs)
    unsaturated = np.logical_not(saturated)
    rl = np.zeros(out.shape, dtype=np.float)
    rl[saturated] = rt[saturated] - rs[saturated]
    rl[unsaturated] = 0
    rv[saturated] = rs[saturated]
    rv[unsaturated] = rt[unsaturated]
    out[saturated] = t[saturated] * (1. + 0.611 * rs[saturated] -
                                     rl[saturated])
    out[unsaturated] = t[unsaturated] * (1. + 0.611 * rt[unsaturated])
    out = t * (1 + rv / tc.EPS) / (1. + rt)
    if isscalar:
        out = out[0]
    return out
Exemple #3
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def tro_trtp(t,rt,pressKpa):
    """in: t=temperature (K),pressKpa= pressure (kPa)
           rt=mixing ratio (kg/kg)
       out:tro=density temperature (K)  (vector)
    """
    isscalar = test_scalar(t,rt,pressKpa)
    if not isscalar:
        t=np.atleast_1d(t)
        rt=np.atleast_1d(rt)
        rv=np.empty_like(rt)
        pressKpa=np.atleast_1d(pressKpa)
    rs=rs_tp(t,pressKpa)
    out=np.empty(rs.shape,dtype=np.float)
    saturated = (rt>=rs)
    unsaturated=np.logical_not(saturated)
    rl=np.zeros(out.shape,dtype=np.float)
    rl[saturated]=rt[saturated] - rs[saturated]
    rl[unsaturated]=0
    rv[saturated]=rs[saturated]
    rv[unsaturated]=rt[unsaturated]
    out[saturated]=t[saturated]*(1.+0.611*rs[saturated]-rl[saturated])
    out[unsaturated]=t[unsaturated]*(1.+ 0.611*rt[unsaturated])
    out=t*(1 + rv/tc.EPS)/(1. + rt)
    if isscalar:
        out=out[0]
    return out
Exemple #4
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def thetal(press,Temp,rt):
    """
    input: press in kPa  (1d vector or scalar)
           temp in K  (1d vector or scalar
           mixing ratio in kg/kg  (1d vector or scalar)
    # emanuel p. 121  4.5.15
    """
    isscalar = test_scalar(press,Temp,rt)
    press=np.atleast_1d(press)
    Temp=np.atleast_1d(Temp)
    rt = np.atleast_1d(rt)
    rl=np.empty_like(rt)
    rsat=rs_tp(Temp,press)
    CPn=tc.RD + rt*tc.RV
    chi=CPn/(tc.CPD + rt*tc.CPV)
    gamma=(rt*tc.RV)/CPn
    saturated=rt > rsat
    rl[saturated]=rt[saturated] - rsat[saturated]
    unsaturated=np.logical_not(saturated)
    rl[unsaturated]=0
    LV=L_t(Temp)
    theta=Temp*(tc.P0/press)**chi
    term1=(1. - rl/(tc.EPS + rt))**chi
    term2=(1 - rl/rt)**(-gamma)
    term3= -LV*rl/(CPn*Temp)
    term3=np.exp(term3)
    theThetal=theta*term1*term2*term3
    if isscalar:
        theThetal = theThetal[0]
    return theThetal
Exemple #5
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def alt_thetal(press, Temp, qt):
    """
    quicker approximate version of thetal
    input: press in kPa  (1d vector or scalar)
           temp in K  (1d vector or scalar
           mixing ratio in kg/kg  (1d vector or scalar)
    """
    isscalar = test_scalar(press, Temp, qt)
    press = np.atleast_1d(press)
    Temp = np.atleast_1d(Temp)
    qt = np.atleast_1d(qt)
    ql = np.empty_like(qt)
    qsat = qs_tp(Temp, press)
    ql = qt - qsat
    ql[ql < 0] = 0.0
    theta = Temp * (100.0 / press) ** 0.288
    L = 2.5e6
    cpd = 1004.0
    the_thetal = theta - (theta / Temp) * (L / cpd) * ql
    if isscalar:
        the_thetal = the_thetal[0]
    return the_thetal