The Human Impacts Database

A collection of useful numbers for quantifying the impacts of the human presence on Earth.

Annual Northern Hemisphere sea ice area loss

WaterCryosphere

This quantity is a single measurement of the quantity at a given point in time (1979-2021).

Value:

This is equivalent to...

-2.45 × 104 km2 / yr

-0.42 × 1010 m2 / yr at yearly maximum cover (March)

-0.42 × 104 km2 / yr at yearly maximum cover (March)

-4.82 × 1010 m2 / yr at yearly minimum cover (September)

-4.82 × 104 km2 / yr at yearly minimum cover (September)
HuID: 66277
Relevant Year(s): 1979-2021
Summary: This entry represents the annualized trend of sea ice area lost from the Northern Hemisphere from 1979-2021. The entry gives three values calculated for different periods: 1) the annualized trend for the yearly sea ice area change, 2) the annualized trend for the sea ice area change in the month of maximum average area over the period 1979-2021 (March), and 3) the annualized trend for the sea ice area change in the month of minimum average area over the period 1979-2021 (September).
Method: The Sea Ice Index provides satellite data for sea ice cover described as sea ice extent (calculated by taking the integral sum of the areas within grid cells with > 15% ice concentration) and area (calculated by multiplying the percentage of sea ice in each grid cell with > 15% ice concentration by the area of the grid cell and taking the integral sum of these products) in the northern and southern hemispheres from 1979-2021. This entry represents sea ice area. The annualized yearly trend provided represents the linear trend calculated from the average annual area. The annualized monthly trends for March and September represent the linear trends calculated from the average monthly area in the respective months.
Source: Fetterer, F., K. Knowles, W. N. Meier, M. Savoie, and A. K. Windnagel. 2017, updated daily. Boulder, Colorado USA. NSIDC: National Snow and Ice Data Center. doi: https://doi.org/10.7265/N5K072F8. [2022-Feb-16]. Sea_Ice_Index_Monthly_Data_by_Year_G02135_v3.0.xlsx. (2017)
Dataset: This file gives the calculated linear trend of annualized sea ice area loss for each month from 1979-2019. (northern_hemisphere_area_change.csv)
regional resolution
Original Data License: NSIDC Open Data Policy
Added By: nsarai