function yy=qair(y)
t=y(:,1);%temp
p=y(:,2);%pressure
h=y(:,3);%rel humidity (dimensionless)
es=h.*6.1121.*exp(17.502.*t./(t+240.970)).*(1.0007+3.46e-6*p);
yy=es.*621.97./(p-.378*es);