Radiative and nonradiative decay rates of the C2Σ+u electronic state of N+2 are calculated as a function of the temperature. This makes it possible to study the effect of the temperature on the photoemission spectrum and on the ion yields I(N+) and I(N+2). It is shown that the temperature has different effects on the isotopes 28N+2, 29N+2, and 30N+2. Our results confirm that, regardless of the temperature, predissociation is the dominant relaxation mechanism for vibrational states ν′⩾3 of the 28N+2 and 29N+2 molecules.