Abstract
The Gulf Stream is expected to slow and shift poleward over the next
century due to climate change. We investigate whether such changes are
already observable in the altimetric record (1993–2018) using
along-track altimetry. Trends in latitude, speed, transport, and width
are calculated in stream-following coordinates to avoid aliasing
possible increases in variability into changes in the Stream’s intrinsic
structure. Statistically significant trends are few and apparently
randomly distributed. Further, small changes to the length of the record
lead to large changes in the trends and their significance. These
results indicate that the probability there have been systematic change
in the properties considered is low. Assuming that there may be physical
reasons for the trends, we estimate that 22–23 additional years of
observations are required detect trends in latitude and transport, and
54 additional years for trends in speed for at least half of the
altimetry tracks.