Use the errorbar function on the line of your choice. The easiest way to do this is to plot that line, then use hold to plot the others:
figure(1) errorbar(Traffic, EngsetPb, barvector) hold on plot( ... the rest ... ) hold off grid
Hypothetical variables here.
Do you have the Statistics Toolbox?
x = 1:10; y = sin(x); e = std(y)*ones(size(x));
plot(x,y,'b') hold on errorbar(x,y,e,'bo','markerfacecolor',[0 0 1])
Not sure exactly what you mean by "between red and green graphs"
I'm assuming that each data point is an estimate and you have an associated confidence inteval that you want to represent