void
trace_wetbulb (short width)
/*************************************************************/
/* TRACE_WETBULB */
/* John Hart NSSFC KCMO */
/* */
/* Plots environmental Wetbulb trace on SkewT. */
/*************************************************************/
{
short i, x, y, xold, yold, ok = 0;
float t1;
setlinestyle (1, width);
for (i = 0; i < sndgp->numlev; i++)
{
if (sndgp->sndg[i].dwpt > -200)
{
xold = x;
yold = y;
t1 =
wetbulb (sndgp->sndg[i].pres, sndgp->sndg[i].temp,
sndgp->sndg[i].dwpt);
x = temp_to_pix (t1, sndgp->sndg[i].pres);
y = pres_to_pix (sndgp->sndg[i].pres);
if (ok == 0)
{
moveto (x, y);
ok = 1;
}
else
{
moveto (xold, yold);
lineto (x, y);
}
}
}
}
/*NP*/
void posneg_wetbulb(float start, float *pos, float *neg, float *top, float *bot)
/***********************************************************************/
/* POSNEG */
/* Calculates positive and negative areas as related to winter weather */
/* forecasting. Search begins at 500mb, but only returns results if */
/* a positive area is found, overlaying a negative area. */
/* START is the upper limit of search.(default=init_phase) */
/***********************************************************************/
{
float upper, lower, pe1, h1, te1, tp1, totp, totn, pe2, h2, te2,
tp2, tdef1, tdef2;
float lyrlast, lyre, tote, pelast, ptop, pbot, lvl;
short i, lptr, uptr, warmlayer=0, coldlayer=0, phase;
short pIndex, zIndex, tdIndex;
char st[80];
*pos = 0;
*neg = 0;
*top = 0;
*bot = 0;
/* ----- If there is no sounding, do not compute ----- */
if (!qc(i_temp(500, I_PRES)) && !qc(i_temp(850, I_PRES)))
return;
pIndex = getParmIndex("PRES");
zIndex = getParmIndex("HGHT");
tdIndex = getParmIndex("DWPT");
if (!sndg || pIndex == -1 || zIndex == -1 || tdIndex == -1)
return;
/* ----- Find lowest observation in layer ----- */
lower = sndg[sfc()][pIndex];
lptr = sfc();
/* ----- Find highest observation in layer ----- */
if (start=-1) {
strcpy( st, init_phase( &lvl, &phase ));
if (lvl> 0)
{ upper = lvl; }
else
{ upper=500; }
}
else {
upper = start;
}
i=numlvl-1;
while (sndg[i][pIndex] < upper) {
i--;
if (i < 0) {
fprintf(stderr,
"Warning: posneg_wetbulb: Could not find a pressure greater than %.2f\n",
upper);
fprintf(stderr, "Using %.2f as the upper level.\n",
sndg[0][pIndex]);
i = 0;
break;
}
}
uptr = i;
if (sndg[i][pIndex] == upper)
uptr--;
/* ----- Start with top layer ----- */
pe1 = upper;
h1 = i_hght(pe1 , I_PRES);
te1 = wetbulb(pe1, i_temp(pe1, I_PRES), i_dwpt(pe1, I_PRES));
tp1 = 0;
totp = totn = tote = ptop = pbot = 0;
for( i = uptr; i >= lptr; i-- ) {
if (qc(sndg[i][tdIndex])) {
/* ----- Calculate every level that reports a temp ----- */
pe2 = sndg[i][pIndex];
h2 = sndg[i][zIndex];
te2 = wetbulb(pe2, i_temp(pe2, I_PRES), i_dwpt(pe2, I_PRES));
tp2 = 0;
tdef1 = (0 - te1) / (te1 + 273.15);
tdef2 = (0 - te2) / (te2 + 273.15);
lyrlast = lyre;
lyre = 9.8F * (tdef1 + tdef2) / 2.0F * (h2 - h1);
/* Has a warm layer been found yet? */
if (te2>0)
if (warmlayer==0) {
warmlayer=1;
ptop=pe2;
}
/* Has a cold layer been found yet? */
if (te2<0)
if ((warmlayer==1) && (coldlayer==0)) {
coldlayer=1;
pbot=pe2;
}
if (warmlayer>0) {
if (lyre>0) {
totp += lyre;
}
else {
totn += lyre;
}
tote += lyre;
printf("%4.0f - %4.0f E=%6.0f TOT=%6.0f Top=%6.0f Bot=%6.0f\n",
pe1, pe2, lyre, tote, ptop, pbot);
}
pelast = pe1;
pe1 = pe2;
h1 = h2;
te1 = te2;
tp1 = tp2;
}
}
if ((warmlayer==1) && (coldlayer==1)) {
*pos = totp;
*neg = totn;
*top = ptop;
*bot = pbot;
printf("Tot= %.0f J/kg Pos= %.0f J/kg Neg= %.0f J/kg\n",
tote, totp, totn);
printf("Top= %.0f Bot= %.0f\n", ptop, pbot);
}
else {
printf("Warm/Cold Layers not found.\n" );
*pos = 0;
*neg = 0;
*top = 0;
*bot = 0;
}
}
