Carrigan attended Girton College, Cambridge, graduating with a BA in English, winning Girton's Charity Reeves Prize in English and an Emily Davies Scholarship in 2001. He took his MA at the School of Advanced Study, University of London. He completed his PhD thesis, Representations of Tourism in Postcolonial Island Literatures in the School of English at the University of Leeds, in 2008.
Following his PhD, Carrigan took up a lectureship at Keele University in 2009, in the course of which he also held a fellowship at the Rachel Carson Center for Environment and Society at Ludwig-Maximilians-Universität in Munich (January–June 2012).
Carrigan is best known for his 2011 monograph Postcolonial Tourism: Literature, Culture, and Environment. The study was innovative in examining tourism from a postcolonial perspective, and for its argument that "postcolonial literature can shed light on current tourism practices in island states and provide ways for local residents to negotiate a form of sustainable and emancipatory tourism from within the tourism system".
He was described in 2012 as "a lively and authoritative new voice in postcolonial studies".
In September 2013 he returned to the School of English at Leeds University as a lecturer in postcolonial literature and cultures, where he worked until his death in Manchester following an extended period of illness from cancer in 2016, at the age of 35.
Carrigan was an active supporter of the Bhopal Medical Appeal. In June 2016, a special issue of the Journal of Commonwealth Literature on 'postcolonial environments' was dedicated to him. A section of the conference The Future of Wild Europe in September of that year was also dedicated to him.