Arctic Ice in Surplus June 2023

The animation shows Arctic ice extents on day 151 (end of May) through yesterday June 30, 2023 As usual, the Pacific basins Bering and Okhotsk (far left) became ice-free and are no longer included in these updates. Years vary as to which regions retain more or less ice. For example, this year Hudson Bay (bottom right) lost half its ice by June 30, earlier than average. That is a shallow basin and can quickly lose its ice in coming days. Despite this early melting, the NH Ice extent remains greater than the 17 year average.

The graph below compares the June monthly ice extents 2007 to 2023 and compared to the SII 17 year average.

Clearly June ice appears as a plateau, and most years MASIE shows greater extents than SII, with differences of only a few 100k km2. Previously 2019-10 in deficit to average, but June 2022-3 have returned to surplus years. More on MASIE dataset at the end.

The graph shows the melting pattern during June 2023 remained above average all month, and greatly exceeded 2007 and 2020, especially in the last 2 weeks. June 30, 2023 was 322k km2 in surplus, and exceeded 2007 by 0.4 Wadhams (M km2).

The table below shows ice extents by regions comparing 2023 with 17-year average (2006 to 2022 inclusive) and 2007.

Region	2023181	Day 181 Average	2023-Ave.	2007181	2023-2007
(0) Northern_Hemisphere	10072140	9750262	321878	9672969	399171
(1) Beaufort_Sea	919937	927608	-7671	939209	-19272
(2) Chukchi_Sea	804545	723247	81299	670088	134457
(3) East_Siberian_Sea	1021758	1010088	11669	901963	119795
(4) Laptev_Sea	738148	699906	38242	658742	79406
(5) Kara_Sea	568642	542617	26025	657478	-88836
(6) Barents_Sea	99262	117038	-17776	130101	-30839
(7) Greenland_Sea	650550	499950	150600	548399	102152
(8) Baffin_Bay_Gulf_of_St._Lawrence	703359	513540	189819	450461	252898
(9) Canadian_Archipelago	743003	780546	-37543	773611	-30607
(10) Hudson_Bay	577518	707353	-129835	718441	-140923
(11) Central_Arctic	3241230	3204305	36925	3218999	22231

2023 is 322k km2 above average (3.3%). The main deficit is in Hudson Bay, more than offset by large surpluses in Baffin Bay and Greenland Sea, along with additonal ice elsewhere.

Footnote on MASIE Data Sources:

MASIE reports are based on data primarily from NIC’s Interactive Multisensor Snow and Ice Mapping System (IMS). From the documentation, the multiple sources feeding IMS are:

Platform(s) AQUA, DMSP, DMSP 5D-3/F17, GOES-10, GOES-11, GOES-13, GOES-9, METEOSAT, MSG, MTSAT-1R, MTSAT-2, NOAA-14, NOAA-15, NOAA-16, NOAA-17, NOAA-18, NOAA-N, RADARSAT-2, SUOMI-NPP, TERRA

Sensor(s): AMSU-A, ATMS, AVHRR, GOES I-M IMAGER, MODIS, MTSAT 1R Imager, MTSAT 2 Imager, MVIRI, SAR, SEVIRI, SSM/I, SSMIS, VIIRS

Summary: IMS Daily Northern Hemisphere Snow and Ice Analysis

The National Oceanic and Atmospheric Administration / National Environmental Satellite, Data, and Information Service (NOAA/NESDIS) has an extensive history of monitoring snow and ice coverage.Accurate monitoring of global snow/ice cover is a key component in the study of climate and global change as well as daily weather forecasting.

The Polar and Geostationary Operational Environmental Satellite programs (POES/GOES) operated by NESDIS provide invaluable visible and infrared spectral data in support of these efforts. Clear-sky imagery from both the POES and the GOES sensors show snow/ice boundaries very well; however, the visible and infrared techniques may suffer from persistent cloud cover near the snowline, making observations difficult (Ramsay, 1995). The microwave products (DMSP and AMSR-E) are unobstructed by clouds and thus can be used as another observational platform in most regions. Synthetic Aperture Radar (SAR) imagery also provides all-weather, near daily capacities to discriminate sea and lake ice. With several other derived snow/ice products of varying accuracy, such as those from NCEP and the NWS NOHRSC, it is highly desirable for analysts to be able to interactively compare and contrast the products so that a more accurate composite map can be produced.

The Satellite Analysis Branch (SAB) of NESDIS first began generating Northern Hemisphere Weekly Snow and Ice Cover analysis charts derived from the visible satellite imagery in November, 1966. The spatial and temporal resolutions of the analysis (190 km and 7 days, respectively) remained unchanged for the product’s 33-year lifespan.

As a result of increasing customer needs and expectations, it was decided that an efficient, interactive workstation application should be constructed which would enable SAB to produce snow/ice analyses at a higher resolution and on a daily basis (~25 km / 1024 x 1024 grid and once per day) using a consolidated array of new as well as existing satellite and surface imagery products. The Daily Northern Hemisphere Snow and Ice Cover chart has been produced since February, 1997 by SAB meteorologists on the IMS.

Another large resolution improvement began in early 2004, when improved technology allowed the SAB to begin creation of a daily ~4 km (6144×6144) grid. At this time, both the ~4 km and ~24 km products are available from NSIDC with a slight delay. Near real-time gridded data is available in ASCII format by request.

In March 2008, the product was migrated from SAB to the National Ice Center (NIC) of NESDIS. The production system and methodology was preserved during the migration. Improved access to DMSP, SAR, and modeled data sources is expected as a short-term from the migration, with longer term plans of twice daily production, GRIB2 output format, a Southern Hemisphere analysis, and an expanded suite of integrated snow and ice variable on horizon. Source: Interactive Multisensor Snow and Ice Mapping System (IMS)