NYC's Glacial Past: Evidence of Ancient Ice Sheets in New York City

Ancient Glaciers in New York City

• ❄️ Approximately 20,000 years ago, New York City was covered by glaciers that were 1,000 to 2,000 ft thick.
• 🧊 In some parts of New York State, ice extended over 1.5 miles thick, far exceeding the height of One World Trade Center.

Evidence of Glacial Movement

• 🪨 Glacial evidence, such as smoothed and rounded rocks, can be found throughout the city, including Central Park and Staten Island.
• ✍️ Glacial striations, appearing as scratches on rocks, indicate the direction of ice movement.
• ⛰️ Rounded hills and carved riverbeds, like those by the Hudson River, are also results of glacial activity.

Glacial Erratics and Unique Features

• 🪨 A glacial erratic is a rock transported by a glacier and deposited in its current location upon melting, like a large upright rock found in Central Park.
• 💎 Unique pink granite boulders, uncommon in the area, have been found as far south as the Bronx Zoo, serving as reminders of glacial deposition.

Climate Change and Rising Sea Levels

• 🌊 The melting of glaciers contributes to rising ocean and tide levels, a phenomenon observed with a tide gauge at the Staten Island Ferry terminal.
• ⚠️ New York City officials have been working for years to combat the consequences of a warming climate and rising waters.