Satellite data shows up climate forecasts

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A detailed report by The Washington Post revealed that coastal communities across eight states in the U.S. are facing "one of the most rapid sea level surges on Earth." Since 2010, satellite data shows that the Gulf of Mexico has experienced twice the global average rate of rising sea levels, with more than a dozen tide gauges spanning from Texas to North Carolina registering sea levels that are at least six inches higher than they were 14 years ago.

While many understandably assume that extreme weather events like hurricanes are the source of these changes, experts revealed that rising water levels face a "newer, more insidious challenge" of accumulation caused by smaller-scale weather events.

"To me, here's the story: We are preparing for the wrong disaster almost everywhere," said Rob Young, a professor at Western Carolina University and director of the Program for the Study of Developed Shorelines. "These smaller changes will be a greater threat over time than the next hurricane, no question about it."

Charleston, South Carolina recorded its fourth-highest water level since measurements began in 1899, with the city's average rising by seven inches since 2010. Jacksonville, Florida has seen an increase of six inches during that period, but Galveston, Texas experienced a whopping eight-inch increase in 14 years.

Last summer, marked by deadly extreme heat and devastating wildfires, was the warmest in at least 2,000 years, according to new research, which analyzed weather data and tree rings to reconstruct a detailed picture of the past.

The findings offer a stark insight into the “unparalleled” warming the world is experiencing today thanks to humans burning vast amounts of planet-heating fossil fuels, according to the authors of the study published Tuesday in the Journal Nature. And it’s an alarming signal as some scientists warn 2024 is on track to be even hotter still.

Global warming is currently tracked by comparing temperatures to the “pre-industrial era,” before humans started burning large amounts of fossil fuels, widely defined as the period between 1850 to 1900. Under the Paris Agreement in 2015, countries agreed to restrict global warming to 2 degrees above pre-industrial levels.

Last summer, the world temporarily breached this threshold, according to the report. Using data taken from temperature instruments during this period, the scientists found the Northern Hemisphere summer in 2023 was 2.07 degrees Celsius warmer than the pre-industrial period.

But observational data from this period is sparse, uncertain and skews warmer. So, for a fuller picture of how the climate varied naturally before the start of the pre-industrial era, the study authors looked much further into the past.

To do this, they used detailed sets of tree ring records from thousands of trees across nine regions of the Northern Hemisphere, including North America and Scandinavia, but excluding the Tropics which lack good tree data.

Trees act as time capsules. The patterns of their rings – affected by sunlight, rainfall and temperature – provide a climate history for each year of their lives, going back centuries or even thousands of years.

This complex tree ring data allowed the scientists to reconstruct annual temperatures for Northern Hemisphere summers between the years 1 and 1849 and compare them to last summer’s temperatures.

They found the summer of 2023 was warmer than any other summer during this period.

It was at least 0.5 degrees Celsius warmer than the warmest summer during this period, the year 246 – when the Roman Empire still ruled over Europe and the Mayan Civilization dominated Central America.

At the other end of the scale, last summer was nearly 4 degrees Celsius warmer than the coldest summer the study identified, the year 536 – when a volcanic eruption pumped out vast amounts of planet-cooling gases.

Using this 2,000-year data set, they calculated that the summer of 2023 was 2.2 degrees Celsius hotter than the long-term pre-industrial average, before robust networks of instruments could measure the weather.

The study follows a report published in November, which found humanity lived through the hottest 12-month period in at least 125,000 years. The study, and others like it, rely on data extracted from other proxies, such as ice cores and coral reefs, which don’t give the same detailed yearly evidence as tree rings.

India’s capital territory of Delhi sweltered to its highest-ever temperature of 49.9 degrees Celsius (121.8 degrees Fahrenheit) on Tuesday, as an oppressive heat wave forced authorities to impose water rationing.

The Indian Meteorological Department (IMD) said the new record was measured in the suburb of Mungeshpur, surpassing Delhi’s previous high of 49.2 degrees Celsius (120.5 degrees Fahrenheit), observed in May 2022.

Some areas of Delhi are struggling to access water, while others have none at all, said Atishi Marlena Singh, a senior minister in the Delhi government, at a news conference.

Areas that normally receive water supplies twice a day will now have their delivery cut to once a day to redirect resources to areas that have had little to no supply at all, Singh said.

The water shortages were caused by the “acute heatwave,” as well as a lack of water deliveries from the northern state of Haryana to Delhi, which are not being made as usual, Singh said.

Rivers and streams in Alaska are changing color – from a clean, clear blue to a rusty orange – because of the toxic metals released by thawing permafrost, according to a new study.

The finding surprised researchers from the National Park Service, the University of California at Davis and the US Geological Survey, who conducted tests at 75 locations in the waterways of Alaska’s Brooks Range. The rivers and streams in the range appeared to rust and became cloudy and orange over the past five to 10 years, according to the study published in the journal Communications: Earth & Environment.

The discoloration and cloudiness are being caused by metals such as iron, zinc, copper, nickel and lead, the researchers found – some of which are toxic to the river and stream ecosystems – as permafrost thaws and exposes the waterways to minerals locked away underground for thousands of years.

“We’re used to seeing this in parts of California, parts of Appalachia where we have mining history. This is a classic process that happens in rivers here in the continental US that have been impacted for over 100 years since some of the mining rushes in the 1850s,” said Brett Poulin, a co-author of the study and a professor of environmental toxicology at UC Davis.

“But it’s very startling to see it when you’re on some of the most remote wilderness and you’re far from a mine source.”

Arctic soils naturally contain organic carbon, nutrients and metals, such as mercury, within their permafrost, the study says. High temperatures have caused these minerals and the water sources around them to meet as permafrost melts.

The Arctic is warming four times faster than the rest of the world, studies have shown.

“What we believe we’re seeing is this thawing of soil that’s happening faster there than it would happen elsewhere,” said Poulin. “It’s really an unexpected consequence of climate change.”