Method and system for mitigating adverse effects of a gas absorption line in coherent optical communication systems

A network controller, comprising:

• a detector interface configured to receive detection of a narrow-band absorption occurring within a frequency spectrum of an optical signal propagating through a gaseous medium, wherein the optical signal is configured to communicate digital information via an optical communication link of a plurality of optical communication links of a communication network, the optical communication link comprising a transmitter, a receiver and an optical transport medium therebetween;
• and
• a mitigation controller configured to control a digital circuit to mitigate at least a portion of a vulnerability of the optical communication link, the vulnerability associated with the detection of the narrow-band absorption, wherein the detection of the narrow-band absorption is based on a correlation of a spectral occupancy of at least a portion of the frequency spectrum of the optical signal with a predetermined spectrum of a gas absorption line to obtain a correlation result, wherein the detection of the narrow-band absorption is based on the correlation result.