# Clarifying the relationship between pressure and temperature?

From the ideal gas law, we are aware that PV = nRT, which seems to suggest a direct relationship between pressure and temperature, or that as temperature increases, pressure increases.

In my geography book, however, it is written that "The equator receives direct rays of the Sun, this causes the temperature to rise, hence causing an equatorial low-pressure region." Later the book writes that "Colder air causes a higher pressure." Not just this, when I plotted data between sea level pressure, and average temperature for a weather station in New York, the plot I got was this which seems totally counter-intuitive to the direct relationship suggested by the ideal gas law.

• as temperature increases, pressure decreases How did you reach that conclusion from $PV=nRT$? Is there a typo? Commented Jul 22, 2020 at 5:25
• Was a typo, edited it Commented Jul 22, 2020 at 5:35

• It's also worth pointing out that ideal gas law is also not true for any real gas at moderate pressure and temperature. Though, the relationships are generally quite similar ($P\uparrow \implies T\uparrow$ when $V$ is constant), but there may not even be an exact mathematical form for it.