New Jersey was the most improved state in the nation for energy efficiency this year, according to the 2018 State Energy Efficiency Scorecard.
The 12th annual report from the American Council for an Energy-Efficient Economy, released Thursday, rated Massachusetts the best and California second best for energy policies.
States that lost ground or lagged behind included Iowa, North Dakota, West Virginia, and Wyoming.
New Jersey improved the most, moving up five ranks to number 18 nationally, the raters said.
The state set new annual energy savings targets to increase use of solar and wind energy and reach 100 percent clean energy by 2050; and took steps to rejoin the Regional Greenhouse Gas Initiative, a multistate cap and trade emissions compact, the group said.
Plants not climate change-saviors we hoped for, according to researchers
Assumptions about how plants will help combat climate change by absorbing increased levels of carbon dioxide turn out to be wrong, according to two studies released last week.
Higher levels of carbon dioxide in the air thickens plant leaves, making plants less effective at holding carbon and worsening climate change, according to University of Washington researchers.
Climate models have not taken leaf thickening into account, according to a paper published Oct. 1 in the journal Global Biogeochemical Cycles.
And plants don’t absorb more carbon dioxide as the growing season starts earlier with climate change, according to a large international study recently published in the journal Nature.
Instead, satellite images of the globe from the past 30 years show that, in many regions, an early spring leads to less overall plant growth, said Matthias Forkel of the Department of Geodesy and Geoinformation at Technische Universität Wien in Vienna, Austria.
The northern hemisphere is greener in the spring when temperatures are especially warm, he said, but that impact can be reversed in summer and autumn, leading to an overall reduction of carbon uptake.
Scientists theorize that greater plant growth in the spring increases the demand for water, decreasing soil moisture. Insufficient water is then available to plants later in the year.
And some plants may be programmed to only grow at certain times, researchers said.
“Unfortunately, this changes climate forecasts for the worse,” said Forkel. “We have to assume that the consequences of global warming will be even more dramatic than previously calculated.”
When the researchers added the information about leaf thickening into global climate models, under high carbon levels expected later this century, plants’ global “carbon sink” was less productive. It left about 6.39 billion more tons of carbon in the atmosphere per year than expected, they reported.
Global temperatures could rise an extra 0.3 to 1.4 degrees Celsius beyond what already has been projected, according to simulations run by Abigail Swann, a UW assistant professor of atmospheric sciences and biology, and Marlies Kovenock, a UW doctoral student in biology.
The concentration of carbon dioxide in the atmosphere today is about 410 parts per million and is projected to hit as much as 900 ppm by the end of the century.
The carbon level that Kovenock and Swann simulated with thickened leaves was 710 ppm.