After her PhD, Johnson began work at
British Antarctic Survey (BAS). The first project she worked on (2002–2005) was an analysis of the origin and implications of
authigenic alteration minerals in
volcaniclastic rocks from
James Ross Island. In 2005–2009, she worked in the QWAD (
Quaternary West Antarctic
Deglaciation project), within the GRADES (Glacial Retreat in Antarctica and Deglaciation of the Earth System) programme at BAS, reconstructing Quaternary thinning history of
Pine Island Glacier. Her work showed that Pine Island Glacier thinned as rapidly 8000 years ago as it is at the present day. From 2015 to 2020, Johnson worked as a principle investigator on a
Natural Environment Research Council (NERC) funded project "Reconstructing millennial-scale ice sheet change in the western
Amundsen Sea Embayment, Antarctica, using high-precision exposure dating", with a team from BAS,
Imperial College London,
Durham University,
Columbia University (USA) and
Pennsylvania State University (USA). She is also working on other projects including • Exploring feedbacks between
glaciation,
volcanism and climate in Antarctica: studying
carbon dioxide outgassing from the James Ross Island lavas using
melt inclusions in
olivines • Determining Quaternary glacial history of the
Lassiter Coast, Antarctica •
Comminution dating boundary conditions: A study of (234U/238U) disequilibrium along the
Antarctic Peninsula • Antarctic Peninsula exhumation and landscape development investigated by low-temperature detrital thermochronometry Some of her research has taken place in remote parts of the
West Antarctic Ice Sheet. From 2018- 2025, Johnson worked as the Lead UK principal investigator for a project within the
International Thwaites Glacier Collaboration. During this time Johnson studied
Thwaites Glacier and its stability in order to find implications on future
sea-level rise.
Publications Her publications and the Columbia University,
Marie Tharp Fellowship for 2010–2011. The three-month fellowship allowed Johnson to collaborate with scientists at
Lamont–Doherty Earth Observatory with the results published in the journal
Science. Johnson was awarded a
Polar medal in the 2023 New Year's Honours list. ==Personal life==