  We want to find the cosmological constant influence on cosmic microwave
background (CMB) temperature due to moving linear cosmic strings. Considering
the space-time metric of a linear cosmic string in an accelerated expanding
universe, the Gott-Kaiser-Stebbins (GKS) effect, as an important mechanism in
producing temperature discontinuity in the CMB, is considered and its
modification due to the effect of the cosmological constant is calculated. The
result shows that a positive cosmological constant (i.e. the presence of cosmic
strings in an accelerated expanding universe) weakens the discontinuity in
temperature so that more strong resolution is needed to detect the
corresponding influences on the CMB power spectrum and anisotropy.
