 DISCUSSION: A teleconnection is a link between weather patterns and changes occurring in widely separated areas of the globe. You know of at least one but may be unaware that it is a teleconnection. Ever heard of El Niño? Anyway, this is a teleconnection. The full name is El Niño Southern Oscillation. First, the Southern Oscillation will be discussed. This is the pressure difference between eastern and western parts of the Pacific Ocean.
How does this effect the weather? Indirectly. Whether the pressure is higher or lower than normal in one area, it will change the direction of surface winds across the ocean. This causes warm or cool water to move, which in turn will affect the weather. The Southern Oscillation indicates El Niño, La Niña, or in some cases, La Nada. El Niño, by definition, is an odd warming of surface ocean water temperatures in the eastern tropical Pacific, off the coasts of Ecuador and northern Peru. It is called El Niño because this condition often occurs around Christmas. This can last for quite some time, for weeks, months, or over a year! Some of the effects of the El Niño are as follows. Convection, where water vapor rises and condenses to form clouds, increases over the eastern Pacific. The north to south temperature gradient over the eastern Pacific increases as well. In addition, there are fewer storms and mild temperatures across the north. Storm tracks tend to shift southward across the United States during El Niño. Finally, there is a reduced flow of air from the polar regions. A La Niña is when sea surface temperatures are cooler than normal in the Pacific because of a strong increase in trade winds. Contrary to El Niño, La Niña causes an absence of convection of the eastern Pacific and sees it shift toward the western Pacific. The temperature gradient mentioned before also diminishes. One of the effects of La Niña has on the United States is that it increases the amount of cold air outbreaks in the North. However, there is variation in temperature and storm activity in the north while the south sees warmer and drier weather. In conclusion, teleconnections can play a massive role in shaping local weather patterns. For more on teleconnections, click here! © 2018 Meteorologist Jennifer Naillon
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Climate Change Threatens Extensive Eradication of Insects and Ecosystem (Credit: The Guardian)5/24/2018  DISCUSSION: Climate change is on track to wipe out almost half of all insect species by the end of the century, according to a recently released report.
The report analyzed the ramifications varying outcomes of climate change would have on 115,000 living species. Professor Rachel Warren of the University of East Anglia (UEA) led the report which found that plants and insects are heavily affected by climate change. Mammals and birds are also affected, but less severely given their ability to migrate more easily. Warren noted that insects are the most sensitive group, meaning they are most vulnerable to widespread decimation if action is not taken in addition to what is already in place. The study found that even with current carbon emission cuts almost half of insect species will be gone by 2100. The loss of insects would be tragic to the ecosystem, especially with the projected loss of species like bees that pollinate many plants. “They are important because ecosystems cannot function without insects. They play an absolutely critical role in the food chain”, said Warren in an interview with The Guardian. The analysis included data on the geographic ranges and current climates of 31,000 insect species, 8,000 birds, 1,000 amphibians, 1,700 mammals, 1,800 reptiles and 71,000 plants. The study looked at how the ranges of species would change when certain areas of the world couldn’t support certain species anymore. The study did this by providing calculations for the ambitious 1.5 degrees Celsius (1.5C) target set in the Paris Climate Agreement, the established 2C target, and 3.2C, which is the track the world is currently on should there be no further intervention to stop climate change. The researchers looked at two variables in the end. They first found that as a result of climate change, 49% of insects would lose their ranges as a result of the 3.2C projection. This was trailed by the 2C threshold at an 18% loss and the 1.5C threshold at a 6% loss. Warren’s team also found that insects will lose on average 43% of their lands should the world warm 3.2C by the end of the century. When specific species are looked at, the team found that pollinating insects are particularly susceptible to losses due to climate change. In 2017, researchers in Germany found that the country had lost three-fourths of flying insects in the past 25 years, prompting the team to conclude that this was happening globally. This prompted many scientists to warn of an “ecological Armageddon”. Professor Dave Goulson of the University of Sussex was not part of the study but does believe that the future of biodiversity on Planet Earth is nonexistent. “When we add in all the other adverse factors affecting wildlife, all likely to increase as the human population grows, the future for biodiversity on planet Earth looks bleak,” said Goulson. Professor Guy Midgley of the University of Stellenbosch in South Africa also gave a grim outlook when referring to the loss of insect species. Midgley noted that this was the most comprehensive of studies on the loss of insects due to climate change projections, yet it still failed to cover the impact of lost interactions between species as ranges change and what effects extreme weather would have on the ecosystem. Due to this, Midgley assumed that the research in the study were underestimates, and the adverse effects would likely be greater. Warren believes that most countries have been aware that this is an issue. “It is the when and how,” Warren said, “which will determine the future of the planet. The question is to what extent greater reductions can be made and on what timescale. That is a decision society has to make.” Already, a study published earlier this month found that one-third of the world’s protected lands, which account for 15% of all land spaces, have now been corrupted by intensive farming, grazing, and urbanization. Professor Kendall Jones, the University of Queensland professor that led the study, concluded that a well-run network of protected land areas is necessary to keep from annihilating species and ecosystems worldwide. For more on how climate change may affect you, click here! ©2018 Weather Forecaster Jacob Dolinger How Increased Oceanic Heat Content May Influence Future Tropical Cyclones. (credit: NCAR/UCAR)5/22/2018  DISCUSSION: It is very well-known and understood throughout the atmospheric science forecasting and research community that tropical cyclones chiefly rely upon a combination of low to moderate vertical wind shear along with warm sea surface temperatures as well as above-average to well above-average upper oceanic heat content to. Tropical cyclones need such a plethora of above-average oceanic heat content since this is the “fuel” which allows tropical cyclones to intensify and/or sustain a given intensity (assuming all other atmospheric parameters/factors remain favorable). Thus, with the prospects of a continued net warming of the Earth’s respective ocean basins, this continues to raise more substantial causes for concerns regarding future tropical cyclone frequency and intensity forecasting.
The reason for such large concerns regarding tropical cyclone frequency and intensity forecasting is chiefly connected to the fact that with a net average increase in the magnitude of upper oceanic heat content, this creates a scenario wherein tropical cyclones will have even more upper oceanic heat content energy to tap into during their lifetimes in many cases. This is a major cause for concern since ever since the Industrial Revolution, and increasingly larger percentage of people have flocked toward coastal regions and set up a permanent way of life in such regions. Thus, an increase in the average maximum potential intensity (MPI) of future tropical cyclones is an alarming precedent to contemplate since there are unimaginable logistical and economic vulnerabilities across coastal regions all over the world. Within the last two decades alone, the world has seen what tropical cyclones including (but certainly not limited to) Hurricane Katrina (2005), Hurricane Rita (2005), Hurricane Wilma (2005), Hurricane Ike (2008), Hurricane Sandy (2012), Hurricane Harvey (2017), Hurricane Irma (2017), and Hurricane Maria (2017) have done to coastal regions just across the United States and Puerto Rico. Hence, considering the prospects of even further MPI increases is a downright scary thing to consider based on the recollection of just the collection of intense tropical cyclones which have slammed parts of the United States just within the past 20 years or so, as noted above. However, regardless of how future MPI changes with storms due to changing oceanic and atmospheric tendencies, it is important to make sure that you are always preparing for the next tropical cyclone threat well before it ever gets close to your hometown (if you live in an area which is prone to tropical cyclone impacts). Have a plan and a way to execute the plan well ahead of danger making itself known. To learn more about this particular story and another directly related story, click on the following website links which are attached here: https://www.npr.org/sections/thetwo-way/2018/05/10/610140149/record-heat-in-the-gulf-fueled-hurricane-harveys-deluge or www2.ucar.edu/atmosnews/news/132662/record-breaking-ocean-heat-fueled-hurricane-harvey?utm_source=AtmosNews&utm_campaign=3b06810369-AtmosNews&utm_medium=email&utm_term=0_80502e816e-3b06810369-93154697. To learn more about other interesting climate issues/topics from around the world, be sure to click here! © 2018 Meteorologist Jordan Rabinowitz  Factors that inflict climatic changes part 3:
Part 2 here DISCUSSION: When thinking about the global climate and factors that affect it, many people often ponder about the more frequently covered issues which include (but are certainly not limited to): greenhouse gases, deforestation and melting of glaciers. But the Earth also contains a more complicated conveyor belt of energy which affects the state of regional climate zones all over the world and this is the Earth’s oceans. Ocean currents play a crucial role in Earth’s climate, for example, either regulating the day-to-day weather of the western United States (and other parts of North America) as well as influencing many parts of northern Europe via the consistent transport of relatively warmer water emanating from the Gulf Stream and the western Caribbean Sea. It is important to acknowledge that approximately two-thirds of the Earth is covered by water, so there is no debate at this point in scientific research that the Earth’s oceans have a substantial impact and influence on the Earth’s global climate. Ocean currents play a crucial role in the oceanic transfer of heat energy between the two hemispheres. More specifically, they play a crucial role in helping to facilitate an effective transport of the seasonal net surplus of tropical heat and moisture from the tropical regions of the world and towards the Polar, Arctic, and Antarctic regions. Differing ocean currents are chiefly driven by varying water densities, differentiating vertical oceanic heat profiles, and the complex interactions which occur between interacting zones of freshwater and salt water of varying concentrations. Ocean currents also play a key role in helping to regulate the global climate and help reinstate balance to the uneven distribution of energy that solar radiation has on regional sea surfaces. For example, even though the Earth typically receives approximately between 1.5 and 2.5% of the Sun’s net energy output, there is often a substantial differential between net uppermost oceanic heat content in looking between the tropics and the mid-latitudes. Thus, since the Earth always seeks a state of both oceanic and atmospheric equilibrium, the oceans help to redistribute the consistent imbalances through the progression of various global ocean currents which transport such regional surpluses of oceanic heat content to other cooler oceanic waters around the world. As shown in the image above, the global oceanic system has a plethora of ocean currents which travel in various directions and possess the role of carrying both warmer and colder water depending on the given ocean current being referenced. An example of one such ocean current is the Atlantic Meridional Overturning Circulation or AMOC. The AMOC is an ocean current which carries warm water from the Southern Hemisphere to Northern Europe. More specifically, warmer water is transported up from the Gulf Stream and into the North Atlantic Ocean before being returned towards the Central Atlantic Ocean. The water being transported to the central Atlantic is colder and denser, so it tends to sink and consequently allows warmer water to rise towards the upper layers of the ocean (a process which is scientifically referred to as upwelling). One of many primary concerns for the future with the prospects of a warming world, is the continued gradual net warming of the North Atlantic Ocean. A pattern chiefly defined by continued gradual warming could potentially create a situation wherein water being transported to the Central Atlantic Ocean could become warmer (and consequently, somewhat less likely to sink in accordance with the overturning southward-directed deep ocean circulation). This could then result in a gradual decrease in the strength and/or magnitude of the AMOC at certain points which could lead to a compromise in the efficiency of the typical net heat transfer being accomplished between various parts of the world. In short, the continued warming of Earth’s oceans will likely trigger changes in the efficiency and magnitude of typical global heat and energy exchanges which are critical to maintain a state of global energy balance. Hence, it will be crucial to continue monitoring the state of the Earth’s oceans (and various currents therein) to see how they evolve as continued changes continued to be applied to coupled atmosphere-ocean system and what threat(s) may be consequently imposed on Earth’s global climate system. An occurrence that often happens with warming temperatures is the melting of freshwater reserves which can often pose a threat to Earth’s global ocean circulation system. The influx of freshwater from melting glaciers and land ice can have consequences and cause the upper-most layer of the ocean to become less dense. Although colder in Polar Regions, freshwater is less dense than salty ocean water. So, paradoxically, as the planet warms, and freshwater reserves melt, regions where warm water is circulated, would likely observe a decrease in sea surface temperatures due to the weakening of various ocean currents. Referring to the AMOC, a recent study by the United States National Academy of Sciences showed that an uneven mixture of fresh and salt water along with warming ocean temperatures could decrease the transport of water by the AMOC between 5 and 48 percent. This seems like a wide range of variability, but it is based upon 19 experiments from five models of climate scenarios. With such an example of a projected decrease in global oceanic energy transport, numerous regions around the Earth could experience corresponding changes to their regional climate due to the lack of middle to upper oceanic water mixing which is why monitoring continued changes (and fluctuations therein) in our global oceanic circulations will remain that much more important as we move deeper into the 21st century. To learn more about the story which inspired this article, click on the following link: https://phys.org/news/2016-03-variability-major-oceanic-currents-driven.html. To also learn more about other interesting global climate topics/issues from around the world, be sure to click here! © 2018 Weather Forecaster Alec Kownacki and Meteorologist Jordan Rabinowitz |
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