Time To Read
Date Last Modified
Place 07 · The Northeast Coast · Chapter 4 of 7
The Fastest-Warming Water
Between 2004 and 2013 the Gulf of Maine warmed faster than 99% of the world’s ocean, and the lobsters noticed before most people did.
About 15 minutes · 1 video · 1 live ocean map · 2 quick activities
Start here
A bathtub with the hot tap on
The Gulf of Maine is a shallow, half-enclosed basin, fenced off from the open Atlantic by Georges Bank. For a long time cold water from the north kept it chilly; lately more warm water has been getting in, partly as the Gulf Stream has shifted north and the cold Labrador supply has weakened. The Gulf of Maine Research Institute’s latest annual report, published in March 2026, puts its surface warming since 1982 at 0.84°F per decade, nearly three times the global ocean average.
Watch this
See it move
Gulf of Maine Research Institute — Gulf of Maine, Explained: Causes & Impacts of Rapid Warming. Three minutes with the director of GMRI’s Climate Center on why this particular corner of the ocean is heating up so fast.
While you watch, look for
- The reasons the Gulf of Maine warms faster than most of the ocean
- Which animals and fisheries are feeling the change
- Something you did not expect. Hold onto it.
The short version
Three things going on here
The heat wave
The year the lobsters came early
A marine heat wave is a stretch of unusually warm water that lasts days to months. In 2012 one spread across the Northwest Atlantic, lobster landings started weeks earlier than usual, and the sudden glut sent prices crashing. In 2025 the Gulf logged about 26 heat-wave days, and it was still only its 15th warmest year on record, which tells you how many warm years it has had.
The lobster
A boom that moved north
Lobsters get stressed in water above about 20°C (68°F). From 1996 to 2014, as southern New England warmed, New York’s lobster landings fell 97.7%, and a 1999 die-off in Long Island Sound left about 70% of its lobstermen with no fishing income that year. Meanwhile Maine boomed, peaking around 132 million pounds in 2016, and has slipped since: 78.8 million pounds in 2025, still worth about $461 million.
The newcomers
Who left, who arrived
Northern shrimp, a cold-water species, crashed, and the Gulf of Maine shrimp fishery has been closed since 2014, with the moratorium now extended through 2028. Black sea bass, once most common off North Carolina, are now caught as far north as the Gulf of Maine. Scientists studying hundreds of North American species found that fish tend to follow their preferred temperatures as those temperatures move, a speed called climate velocity.
Photos: David Yu, _ Whittington, Engin Akyurt / Pexels
Play with it
See how unusual today’s water is
This live map shows today’s sea surface temperature anomaly: how much warmer (reds) or cooler (blues) the water is than normal for this time of year. Find the Gulf of Maine, tucked between Cape Cod and Nova Scotia, and click on it to read today’s number.
Live map: earth.nullschool.net by Cameron Beccario, sea surface temperature anomaly from NOAA, ocean currents from OSCAR (Earth & Space Research) and the Copernicus Marine Service.
Two questions to answer while you are in there
- Is the Gulf of Maine warmer or cooler than normal today? Spring 2026 was actually the coolest in more than two decades near the bottom. Does one cool season cancel a 40-year warming trend? Why not?
- Find the warmest-than-normal patch on the map. Is it near the Gulf Stream? What could that mean for the water that gets carried into the Gulf of Maine?
Try it yourself
Check yourself
Try it
From Warmer Water to Shifting Fisheries
Pick the one true statement in each set, and the chain from warm water to empty shrimp nets builds itself.
Try it · interactive
Warming Shift
Drag a year slider from 1980 to 2025 and a warming slider across a Gulf of Maine map, and watch the comfortable water for lobster, cod, northern shrimp and black sea bass move north, shrink or open up.
Open Warming Shift in its own window (opens in a new tab).
Words you will hear
Four terms, that is all
Marine heat wave
Unusually warm ocean water lasting days to months
Thermal tolerance
Range of temperatures a species can survive
Range shift
A species moving where it lives
Climate velocity
Speed and direction a temperature zone moves
Check your understanding
Practice the whole chapter
Everything in this chapter, in eight quick questions. Retry as often as you like. Read the feedback on every answer, right or wrong, because that is where the learning is.
Practice
Practice: The Fastest-Warming Water
Eight questions covering the video, the three cards, the four terms and the interactive above.
If you want more
Go deeper
- Oceanography 101 (MiraCosta) 9.10 — Large Cycles in Ocean Climate Variability — LibreTexts · 6 minutes
- Gulf of Maine Research Institute — 2025 Gulf of Maine Temperature Report — GMRI · 6 minutes
- NOAA Climate.gov — Climate & Lobsters — NOAA · 6 minutes
Photo credits (Pexels): Matthis Volquardsen, Robert Schrader, David Yu, _ Whittington, Engin Akyurt.