At a Glance

This year was the second warmest Arctic year on record, according to the NOAA report. Changes in the Arctic are causing severe weather events in other parts of the world. The number of caribou and reindeer have fallen from 4.7 million to 2.1 million.The Arctic is seeing more harmful algae blooms that can be toxic to wildlife and humans.

This year in the Arctic, surface air temperatures have continued to warm about twice as fast as the rest of the globe, and it was the second warmest year on record since 1900, according to the 13th annual .

In addition, all five years since 2014 have been warmer than any previous records.

“The Arctic is experiencing the most unprecedented transition in history,” said Emily Osborne, lead editor of the report and manager of the National Oceanic and Atmospheric Administration Arctic Research Program.

That warming has ramifications for other parts of the world far from the Arctic.

For example, the warmer Arctic air results in a "sluggish and unusually wavy jet-stream" the report's scientists said. That coincided with extreme weather events in other parts of the planet, includingin 2018, and the extreme cold outbreak in Europe in March 2018 known as "."

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More than 80 scientists from 12 countries contributed to the NOAA report, which was released Tuesday at the American Geophysical Union conference in Washington, D.C.

"Continued warming of the Arctic atmosphere and ocean are driving broad change in the environmental system in predicted and, also, unexpected ways," the report said. "New emerging threats are taking form and highlighting the level of uncertainty in the breadth of environmental change that is to come."

Other highlights from the report include:

The warming Arctic Ocean is seeing an expansion of harmful toxic algal blooms that threaten food sources. Toxins from the blooms accumulate in shellfish or fish and could reach levels that can be lethal to other wildlife and to humans.

Arctic sea ice remained younger, thinner, and covered less area than in the past. That matters because thicker, older ice is more resilient to changes in atmospheric and oceanic heat content than thinner ice, the report says.

The 2018 Arctic Report Card found the Arctic region had the second-lowest overall sea-ice coverage on record. The map shows the age of sea ice in the Arctic ice pack in March 1985, left, and in March 2018, right. Ice that is less than a year old is the darkest blue. Ice that has survived at least four full years is white.

(NOAA Climate.gov/Mark Tschudi./University of Colorado/CCAR)

Atmospheric warming continued to drive broad, long-term trends in declining snow cover, melting of the Greenland Ice Sheet and lake ice, increasing summertime Arctic river discharge, and the expansion and greening of Arctic tundra vegetation.

Even though the amount of vegetation increased, the number of caribou and wild reindeer across the Arctic tundra declined by 56 percent — 4.7 million to 2.1 million — over the past two decades. The loss of those animals threatens the food security and culture of indigenous people who have depended on the herds. Caribou and wild reindeer also are a key species in the Arctic food chain.

(MORE: )Microplastic contamination is on the rise in the Arctic, posing a threat to seabirds and marine life that can ingest tiny particles. Microplastics have been found in Arctic sea ice in much higher concentrations than in global ocean waters. The micro-sized particles can easily be consumed by organisms at lower levels of the food web, causing great accumulation in higher-level consumer organisms.

Susan M. Natali, an Arctic scientist at Woods Hole Research Center in Massachusetts who was not involved in the research, told the New York Times .

“Every time you see a report, things get worse, and we’re still not taking any action," she said. "It adds support that these changes are happening, that they are observable.”