Every Earth Day, which began in 1970 and is observed on April 22, we are bombarded with messages about the state of the planet, what humans are doing to it, and how we can be better stewards of the environment.

With respect to the warming climate, there is good news and bad news.

Each of the last 10 years has been among the 10 warmest on record globally, and last year was the warmest of those ten. Numerous lines of physical evidence indicate the burning of fossil fuels for energy is the root cause.

In the shorter term, each of the last 10 months has also been its warmest on record. Not coincidentally, 2023 also saw a jump in the average temperature of the world’s oceans. Because it takes more energy to raise the temperature of water than land, this sudden increase has many scientists looking for answers.

Data: NOAA, NASA. Graphic: Climate Central

In an article last month from the publication "Nature," the director of the NASA Goddard Institute for Space Studies, Gavin Schmidt, was searching for a definitive reason for the jump. “Many reasons for this discrepancy have been proposed but, as yet, no combination of them has been able to reconcile our theories with what has happened,” Schmidt wrote.

Similarly, studies continue regarding a key ocean circulation that moves warm ocean water from the East Coast toward the colder North Atlantic. This circulation keeps most of Europe from having a much colder climate given its latitude. Most of the data indicate that circulation is slowing.

Stefan Rahmstorf, a scientist at the Potsdam Institute for Climate Impact Research in Germany, has been studying the circulation for 30 years. This month in "Oceanography," he indicated that there are “multiple lines of evidence” to indicate the recent slowing of the circulation is a result of planetary warming from the burning of coal, oil and natural gas.

While it is not something that would happen in a matter of days or months, a full shutdown of that circulation would undoubtedly modify weather patterns. Europe would not go into an ice age, but it certainly would be colder. Early evidence also suggests it would lead to faster sea level rise on the East Coast and much drier islands in the Caribbean Sea.

While not immediately obvious, the movement away from fossil fuels to renewable energy is already underway, not just for altruistic reasons, but for financial ones.

Data: US EIA. Graphic: Climate Central

Nationally, capacity from wind energy has more than doubled since 2014, with the greatest concentration in the Midwest and the Great Plains where the wind is more consistent than in other parts of the country. Offshore wind is beginning to get a footing, as the supports for 176 wind turbines will begin installation this summer off the Virginia coast.

Solar energy capacity has increased by a factor of eight since 2014, as its costs have dropped dramatically, making it the least expensive energy source now being deployed. Not surprisingly, more than half of the new utility scale solar expected to come online this year are from three sunny states: California, Florida and Texas.

Data: US EIA. Graphic: Climate Central

Utility scale batteries still have a long way to go to make up the difference when the sun does not shine and the wind slows down, and this energy storage capacity is expected to double nationally this year. In the meantime, existing nuclear energy installations may provide steadier background power when the renewable installations are not at peak. But in total, solar and storage installations are expected to account for 81 percent of new U.S. capacity this year.

An additional sign of this change comes in the job sector. According to the International Energy Agency, there has been more job growth in the renewable energy sector versus the fossil fuel sector over the last three years, suggesting there is plenty of work to be done in transforming the nation’s electric grid to one that does not emit pollutants into the atmosphere.

Even with more work to be done, important goals are within reach, so despair is not a good strategy. Nonetheless, there are physical aspects of the climate system that will change irreversibly as the climate warms. Sea level rise is one of them. 

While it is not accurate to say we only have a few years to save the Earth, each bit of planetary warming incrementally makes heat waves more likely and more intense, and it locks us into inescapable sea level rise in the decades that follow.

Like any other planning project, the more we are able to do now, the better off we and our children will be. This effectively mirrors a rule famously invoked at the end of almost any Boy Scout campout — leave it better than you found it.

Learn more about climate concerns from these two episodes of the Across the Sky podcast

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