How is there enough $\ce{O2}$ in the atmosphere to breathe if you are in a desert with no plants?
Look at it this way: According to the American National Center of Atmospheric research, the Earths atmosphere weighs 5.148 x 10^^18 kg., and that atmosphere is composed of about 20.8 to 20.9% oxygen (depending on moisture content of the air). So the Earths atmosphere contains about 1.07 million trillion kgs of oxygen. 

The 7.5 billion (or so) humans on the planet, each converts an average of about 0.73 kg of oxygen per day, converting most of it to exhaled CO2. So the planetary consumption of oxygen by humans, as a percentage of the total available, is about 100 x 0.73 x 10^^9 / 1.07 x 10^^18 %.

That is, about half of one millionth of 1% of the Earths available oxygen, a level of oxygen deficiency that is almost instantly dispelled by turbulent mixing in the troposphere (i.e.by 'weather'). So no, there is no chance of gasping for oxygen in deserts or polar wastes. 

Now gasping for air 8000 metres up a mountain, or in a crowded disco with cigarette smoke and poor ventilation - that is another question!