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Local anecdotes are great if you are old enough to have seen changes, because they are simple and relatable examples. In Christchurch, New Zealand, a notable example for me is that the snow line has receded since I was a child. Low lying ski fields are struggling to stay open. My parents have noticed less snow on the ground during winter at their rural place (they have been there ~30 years). > remember where the sea level was back when I was little and also see where it's at now I am a bit skeptical of that claim! Then again, sea level changes would be difficult to notice in Christchurch because we had fast uplift locally: “these events caused ground motion at the Lyttelton TG [tide gauge], the largest single vertical [earthquake] displacement was >50 mm (cumulative displacement ~110 mm)”[1] and slow uplift probably has occurred too “slow slip events has uplifted sites by up to 0.8 mm/year on average in Wellington and Dunedin”. 150km away the coastline uplifted 2 metres (2 yards)[2], boy was that stinky. I think this quote is interesting: “At interannual and decadal time scales TG records typically show variations in annual means on the order of 5–10 cm and a possible 60-year oscillation of up to 3 cm. Although to estimate the long-term trend in relative sea level (RSL), five to six decades of reliable and essentially complete TG records are typically required, techniques exist that can use sparse data sets. A TG measures the RSL trend or the change in sea level relative to the adjacent land. Independent estimates of the vertical land motion (VLM) are required to estimate the absolute sea level (ASL). Such motion may occur due to tectonic movements, ice mass loading, glacial isostatic adjustment (GIA), or local site instabilities due to, for example, compaction, sedimentation, or water, oil, or gas extraction (Carter et al., ). The stability of a TG site is a critical issue that requires verification (Bevis et al., ) and needs to be considered at both local and regional scales. Historically, many TGs are located in shipping ports where harbor infrastructure is often developed on reclaimed or modified land.”[1]. [1] https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/201... [2] https://earthobservatory.nasa.gov/images/89206/powerful-eart... |