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Jiachuan Wu

Jiachuan Wu is a national interactive journalist for NBC News Digital.

Jiachuan Wu is a national interactive journalist for NBC News Digital.

Latest from Jiachuan Wu

Maps: Wildfire smoke has covered the U.S. for more than a month

Wildfire smoke from Canada captivated the East Coast this week, but data shows that much of the United States has been dealing with smoke since early May.
18d ago

Student, 15, arrested after bringing AR-15 and ammunition to a Phoenix high school, police say

Police arrested a 15-year-old student after he allegedly brought an AR-15 and ammunition to a Phoenix high school on Friday, authorities said.
26d ago

What makes the AR-15 so beloved and so reviled

Calls for a ban on AR-15 semiautomatic rifles escalate after every mass shooting, but many Americans still want to be able to buy the military-grade weapon.

California flooding tracker: See which rivers are overflowing

Heavy snow in 2023 primed California for floods. NBC News is tracking river levels as the snow melts.

“The big melt is now here”: California braces for floods

The state’s high peaks stored historic amounts of snowfall this winter. Now the state’s aging water management systems could be at risk.

Interactive: U.S. air quality improved in 2022. See how your city fared.

New air quality data shows that 8 out of every 10 of the larger cities in the U.S. experienced improvements in average PM2.5 values from 2021 to 2022.

How the government protects bank accounts, in three charts

How the FDIC is able to guarantee money for Silicon Valley Bank and Signature Bank account holders, and how it limits bank failure contagion effects.
85d ago

Norfolk Southern once had the lowest accident rate of major U.S. rail companies. Now it's above average.

Data reviewed by NBC News showed that from 2018 to 2022, Norfolk Southern averaged slightly more accidents per million miles than the other six Class-I railroads.

Where Putin's war stands a year after Russia invaded Ukraine

Breaking down the numbers behind the Russia-Ukraine war, on the anniversary of Vladimir Putin's full-scale invasion.

Turkey’s earthquakes and aftershocks, mapped

More than 100 earthquakes have occurred in Turkey and Syria since Feb. 3.

Bed Bath & Beyond is closing 150 more stores. Here's where they are.

Bed Bath & Beyond said it plans to close another 150 stores as it continues to reorganize its finances.