Climate and environment updates: Biden sets ambitious greenhouse gas emissions goal

Humans are dependent on the land for our very survival. If we can't farm, we don't eat. However, much of that precious soil is in danger due to human-amplified climate change, according to a new report.

In its new report, the U.N. Convention to Combat Desertification (UNCCD) found that 77.6% of the Earth's land has become permanently drier over the last three decades leading up to 2020. During the same period, drylands expanded by more than 1.6 million square miles and now cover more than 40% of the planet (excluding Antarctica).

Drylands are regions characterized by low rainfall and moisture, resulting in scarce water and arid land. Drier land can result in insufficient food production, increased wildfire activity, water scarcity and land degradation, according to the report.

"Unlike droughts—temporary periods of low rainfall—aridity represents a permanent, unrelenting transformation," UNCCD Executive Secretary Ibrahim Thiaw said in a press statement. "Droughts end. When an area's climate becomes drier, however, the ability to return to previous conditions is lost. The drier climates now affecting vast lands across the globe will not return to how they were and this change is redefining life on Earth."

The report says human-amplified climate change is the primary reason for this transformation. The UNCCD finds that greenhouse gas emissions from electricity generation, transportation, industry and land use changes are warming the planet and affecting rainfall, evaporation and plant life. They say those changes create the ideal conditions for increased dryness.

And it's not just dry areas getting drier. The researchers found that more than 7% of global lands were transformed from non-drylands to drylands or from less arid areas to more arid. They warn that another 3% of the world's humid areas could become drylands by the end of the century if we don't reduce greenhouse gas emissions.

"Without concerted efforts, billions face a future marked by hunger, displacement, and economic decline. Yet, by embracing innovative solutions and fostering global solidarity, humanity can rise to meet this challenge. The question is not whether we have the tools to respond—it is whether we have the will to act," Nichole Barger, chair of the UNCCD's science-policy interface, said in a statement.

The report makes several recommendations, including better monitoring, improved land use policies and investing in new water efficiency technologies. But they make it clear that the world must curb global warming if they are to stop the future damage and the threats that come from it.

-ABC News Climate Unit's Matthew Glasser

The Earth produces a lot of heat. Scientists believe our planet's inner core is nearly as hot as the sun. Radioactive particles in rocks slowly decay, constantly replenishing the heat. Geothermal energy harnesses that heat to create energy and warm homes and buildings.

However, geothermal energy isn't widely used despite being clean and renewable. It's expensive and often location-specific, usually near tectonic plate boundaries.

But according to a new report from the International Energy Agency (IEA), geothermal power could become a significant source of electricity for the world. The intergovernmental organization found that "geothermal energy could meet 15% of global electricity demand growth between now and 2050 if project costs continue to decline."

That would be enough power to meet the current demand of the United States and India combined. Unlike wind and solar, the IEA says geothermal can provide 24/7 energy generation. It also has the added benefit of heat production and storage.

"New technologies are opening new horizons for geothermal energy across the globe, offering the possibility of meeting a significant portion of the world's rapidly growing demand for electricity securely and cleanly," IEA Executive Director Fatih Birol said in a press statement.

The IEA says with more financial investment, the cost of geothermal energy could fall by 80%. And at a time when finding workers with green energy skills can be challenging, the report states "up to 80% of the investment required in geothermal involves capacity and skills that are transferrable from existing oil and gas operations."

"Geothermal is a major opportunity to draw on the technology and expertise of the oil and gas industry. Our analysis shows that the growth of geothermal could generate investment worth $1 trillion by 2035," Birol added.

With less than three weeks to go before 2025, global temperatures in November have made it all but certain that 2024 will be the warmest year ever recorded.

According to NOAA's monthly climate assessment, last month was the second warmest November globally, with temperatures 2.41 degrees Fahrenheit above the 20th-century average. Temperatures were above average across much of the world, with Asia experiencing its warmest November ever recorded. Oceania and South America were second-warmest.

Year-to-date, the world is experiencing its warmest period on record. That means there's a more than 99% chance that 2024 will break the yearly temperature record currently held by 2023, according to the National Centers for Environmental Information.

According to NOAA, global tropical cyclone activity matched the long-term record with 12 named storms this year. The Atlantic saw three hurricanes in November, including Rafael, which peaked as a Category 3 storm.

Global sea ice area was the second smallest in 46 years and more than one million square miles less than the 1991-2020 average.

-ABC News Climate Unit's Matthew Glasser

In recent years, wildfire smoke has emerged as a significant cause of diminished air quality across many cities in the United States, according to a new recent study presented at the American Geophysical Union annual meeting in Washington, D.C.

The findings, which have not yet been peer-reviewed, suggest that wildfire smoke can contribute to as much as 50% of annual air pollution in certain parts of the U.S. Regions in Oregon, Nevada, California, Washington, North Dakota and Minnesota were identified as some of the most affected by this smoke-related air pollution.

The researchers say the impact of wildfire smoke doesn't just stop in remote areas; it's also impacting major urban centers. Some of the country's largest cities, including New York, Dallas, Chicago, Atlanta and Washington, D.C., reported significant smoke exposure in 2023. Los Angeles, Phoenix and Riverside experienced their highest smoke levels in 2020. The researchers say this year-to-year variation between locations underscores the unpredictable nature of wildfire seasons and their far-reaching consequences on air quality.

The researchers analyzed data collected from more than 800 particle monitors in over 350 areas, representing nearly 90% of the U.S. population. The team combined data from the NOAA Hazard Mapping System Fire and Smoke Product with surface PM2.5 readings to explore how these smoky days affect overall pollution levels. PM2.5 is a type of particulate matter pollution smaller than human hair that can cause a number of health problems, such as asthma and heart disease.

The results from the study raise important questions about public health and environmental policy, especially as climate change intensifies wildfire seasons. According to a study from researchers at the University of Tasmania, extreme wildfire events have more than doubled in frequency and magnitude globally over the past two decades. And the Environmental Protection Agency has found that the U.S. wildfire season has grown longer and shifted earlier in recent decades due to warmer springs, longer summer dry seasons and drier vegetation.

-ABC News Climate Unit's Matthew Glasser and ABC News Medical Unit's Vinh-Son Nguyen, MD