A seasonably hot & humid weekend with winds continuing to blow in off the Atlantic so not bad at the beaches with a refreshing breeze & afternoon temps. in the upper 80s. We'll go back to southerly & southwest winds much of the upcoming week which will mean the more "traditional" afternoon/early evening showers & storms.
Earth Gauge: Carnivorous Plants Turning Vegetarian?
Excess nutrients, such as nitrogen and phosphorus, can degrade water quality causing low oxygen levels and harmful algal blooms. But, can it turn carnivorous plants into vegetarians? A recent study has shown that excess nutrients in soil are being consumed by these plants and making them “full.” When the plants become full, they eat fewer insects. Some carnivorous plants that call the United States home are the Venus Flytrap, Sundew and various species of pitcher plants.
Tip: Carnivorous plants are beneficial in controlling insect populations, but won’t eat them if they get too full. Mosquitoes can be big pests in the summer, as they thrive off standing water left over after rainfalls. Help reduce the amount of nitrogen and phosphorous in our soils by cleaning up fertilizer spills and reading the label to see when and how much to fertilize.
(Sources: Meghan Neal, NY Daily News, “Pollution is turning carnivorous plants vegetarian”; Botany Society of America, “Carnivorous Plants/Insectivorous Plants”; EPA’s New York City Blog, “Mosquito Management: How to Avoid Mosquitoes in your Backyard”.)
Climate Fact: Heat Waves and Extreme High Daily Low Temperatures
In Brief: A trend of warmer nighttime low temperatures has been documented globally. Over North America there are 50 percent more unusually warm nights than there were 50 years ago.
Heat waves are events with extremely high surface temperature conditions that last for several days. For most of the United States, three days with temperatures above 90 degrees Fahrenheit constitutes a heat wave. Extreme heat accounts for about 1,000 deaths in the United States every year and death rates rise an average of six percent during heat wave episodes. Extreme heat in Europe during the summer of 2003 killed an estimated 25,000 people. Since the early 1950s, extreme heat appears to have become more extreme and more frequent: the most robust trend is the significant increase in the occurrence of the warmest 10 percent (compared to the long-term mean) of nighttime low temperatures. This trend of extremely high daily low temperatures has been documented over 73 percent of Earth’s land area.
A few heat wave related trends to note:
· In North America over the last 50 years, there has been a 50 percent increase in the number of unusually warm nights. Nights that fell into the top tenth percentile in terms of temperature for the climate of the 1950s now fall into the top fifteenth percentile and almost all of this increase has happened since 1975.
· The prevalence of stagnant air conditions during heat waves – air conditions with little or no wind – work to make heat waves worse. Over the second half of the 20th century throughout most of the West, the southern Great Plains and the Southeast, stagnant air conditions were prevalent more the 25 percent of the time during heat waves.
· The frequency of heat waves doubled over the United States during the 20th century.
Many factors go into creating a local heat wave and the large scale atmospheric conditions that create heat waves in one region can favor cooler temperatures in another. Anomalously warm or cool sea surface temperatures in the tropical Pacific and tropical Atlantic Oceans can persist for months and are instrumental in shaping the atmospheric circulation anomalies that lead to heat waves. Scientists looking to predict the likelihood of heat waves during the summer look to these ocean waters for signs during the preceding spring. Other factors such as local soil moisture levels, snow cover anomalies on both local and on a hemispheric scale and even anomalies in Arctic Sea Ice extent have been suggested as important for forecasting heat waves. Less Arctic sea ice, for example, favors slower-moving storm systems over midlatitude regions like the United States, which may serve to prolong heat waves and contribute to stagnant air conditions.
(Sources: Francis, JA and Vavrus, SJ. “Evidence linking Arctic amplification to extreme weather in mid-latitudes.” Geophysical Research Letters 39 (2012): L06801. And United States. Climate Change Science Program. Weather and Climate Extremes in a Changing Climate. Synthesis Assessment Product 3.3: GPO. 2008. Global Climate Change Impacts in the United States, Thomas R. Karl, Jerry M. Melillo, and Thomas C. Peterson,(eds.). Cambridge University Press, 2009 and Patz, JA. et al. “Impact of regional climate change on human health.” Nature 438 (2005): 310-317 and Lau, NC and Nath, MJ. “A Model Study of Heat Waves over North America: Meteorological Aspects and Projections for the 21st Century.” Journal of Climate doi:10.1175/JCLI-D-11-00575.1, in press and Wu, Z et al. “Heat wave frequency variability over North America: Two distinct leading modes.” Journal of Geophysical Research 117 (2012): D02102.)
Climate in the News: Misniewski, Mary. “Relief comes for U.S. Midwest, Northeast following heat wave.” – Reuters, July 8, 2012.
The heat wave is letting up in the Midwest and Northeast, while forecasters are predicting a round of extreme heat for the Western states.
Have a great & safe weekend!