Sea level by city · United States

Sea level rise in Boston: how high will the water get?

+78cm by 2100

Under intermediate emissions, sea level at Boston is projected to rise about 34 cm by 2050 and 78 cm by 2100 compared with 1995–2014 — or 100 cm if emissions stay very high. That is 22 cm more than the global average, mostly because the land around Boston is sinking (subsidence), which adds to the rise in the ocean itself.

2100 · Low emissions (SSP1-2.6)
+63cm
likely 44–87 cm · 25 in
2100 · Intermediate (SSP2-4.5)
+78cm
likely 56–105 cm · 31 in
2100 · Very high emissions (SSP5-8.5)
+100cm
likely 76–134 cm · 40 in

Projected sea level rise at Boston, 2020–2150 (cm vs 1995–2014)

Low emissions (SSP1-2.6)Intermediate (SSP2-4.5)Very high emissions (SSP5-8.5)
50100150cm2020204020602080210021202140
Median projections from the IPCC AR6 sea level dataset at the Boston tide gauge (1 km from the city centre). Medium confidence; includes vertical land motion. Lines show the median; the likely range is in the cards and table.
YearLowIntermediateVery high
2030+17 cm (11–24)+17 cm (11–24)+17 cm (11–24)
2050+33 cm (22–45)+34 cm (24–45)+37 cm (27–48)
2070+47 cm (33–64)+52 cm (38–68)+59 cm (44–77)
2100+63 cm (44–87)+78 cm (56–105)+100 cm (76–134)
2150+88 cm (55–130)+122 cm (81–174)+163 cm (113–231)

What it means for Boston

The average rise is only part of the story. What people notice first is flooding: higher seas let ordinary high tides and storm surges reach further inland. The IPCC projects that extreme sea levels which used to occur once a century will happen at least once a year at more than half of the world's tide gauge locations by 2100.

Sea level will keep rising for centuries even after emissions stop, because the deep ocean keeps warming and ice sheets keep melting. Under very high emissions, rises well beyond these ranges cannot be ruled out if parts of the Antarctic ice sheet become unstable — see tipping points.

To see which streets are at risk, use a local flood map: the projections here can be explored station by station in the NASA Sea Level Projection Tool.

Boston climate in 2050Global sea level todayAll coastal cities

Frequently asked questions

Will Boston be underwater?

Not in the sense of the whole city disappearing this century, but the sea at Boston is projected to rise about 78 cm by 2100 under intermediate emissions (likely range 56–105 cm), and about 100 cm under very high emissions. Low-lying districts face more frequent flooding from high tides and storm surges well before then; whether a specific street floods depends on local elevation and flood defences.

How much will sea level rise in Boston by 2050?

About 34 cm (13 inches) compared with 1995–2014 under an intermediate scenario, with a likely range of 24–45 cm. Up to 2050 the emissions scenarios give similar results, because much of this rise is already locked in.

Why is sea level rise in Boston different from the global average?

Projections at a single coast include vertical land motion (sinking or rising land), changes in ocean currents and the gravitational effects of melting ice sheets. That is 22 cm more than the global average, mostly because the land around Boston is sinking (subsidence), which adds to the rise in the ocean itself.

Source: IPCC AR6 Sea Level Projections (Garner et al. 2021; Fox-Kemper et al. 2021), via the NASA Sea Level Projection Tool. Global averages: IPCC AR6 WG1 Table 9.9.

Licence: CC BY 4.0. Relative sea level change incl. vertical land motion, vs 1995–2014, medium confidence; likely range = 17th–83rd percentile.