The heating of the plasma in the solar atmosphere is discussed within both frameworks of fluid and kinetic drift wave theory .
We show that the basic ingredient necessary for the heating is the presence of density gradients in the direction perpendicular to the magnetic field vector .
Such density gradients are a source of free energy for the excitation of drift waves .
We use only well established basic theory , verified experimentally in laboratory plasmas .
Two mechanisms of the energy exchange and heating are shown to take place simultaneously : one due to the Landau effect in the direction parallel to the magnetic field , and another one , stochastic heating , in the perpendicular direction .
The stochastic heating i ) is due to the electrostatic nature of the waves , ii ) is more effective on ions than on electrons , iii ) acts predominantly in the perpendicular direction , iv ) heats heavy ions more efficiently than lighter ions , and v ) may easily provide a drift wave heating rate that is orders of magnitude above the value that is presently believed to be sufficient for the coronal heating , i.e. , \simeq 6 \cdot 10 ^ { -5 } J/ ( m ^ { 3 } s ) for active regions and \simeq 8 \cdot 10 ^ { -6 } J/ ( m ^ { 3 } s ) for coronal holes .
This heating acts naturally through well known effects that are , however , beyond the current standard models and theories .