Irina is making a cyclonic loop, something that a tropical cyclone does on occasion whenever there are a couple of weather systems that push it in different directions.
This image from NASA's TRMM satellite shows rainfall in the remnants of Tropical Cyclone Irina on March 5 at 2:23 a.m. local time/South Africa. Numerous intense storms in the southern and eastern quadrant were dropping rainfall at a rate of over 50mm per hr / ~2 inches (red). Light to moderate rainfall is depicted in blue and green was falling at a rate between .78 to 1.57 inches (20 to 40 mm) per hour. Credit: Credit: SSAI/NASA, Hal Pierce
On March 5, 2012, Irina's maximum sustained winds had increased to near 50 knots (57.5 mph/92.6 kph), , up from 40 knots (46 mph/74 kph) over the last several days. Forecasters at the Joint Typhoon Warning Center expect Irina to strengthen more at sea over the next day, and then begin to weaken.
Irina is still centered at sea, and parallel to the middle of South Africa on March 5. Irina's center is about 315 nautical miles south-southeast of Maputo, Mozambique, and it was moving to the southeast, but is expected to start curving to the northeast and then northwest as it continues making a loop that will take it back toward a landfall in extreme northeastern South Africa.
What's making it loop? Weather systems in the area are pushing past Irina, acting as guides for the storm to follow. The last weather system that will turn it back to the north is a ridge (elongated area) of high pressure that's strengthening over South Africa will turn Irina to the northwest.
Infrared data from Atmospheric Infrared Sounder (AIRS) instrument on NASA's Aqua satellite showed on March 5, that most of the strongest thunderstorms and heaviest rainfall are occurring in the southern half of the storm. The strongest thunderstorms usually have the highest, and coldest cloud top temperatures, which is what AIRS infrared data reads. When cloud tops exceed the AIRS threshold of -63 Fahrenheit (-52.7 Celsius), the cloud tops are considered strong thunderstorms, and usually they have heavy rainfall. On the northern side of the storm, it's a different story, however, as sinking air on the northern side is preventing thunderstorm development.
NASA's Tropical Rainfall Measuring Mission (TRMM) satellite passed over Irina on March 5, 2012 at 0023 UTC (2:23 a.m. local time/South Africa / 7:23 p.m. EST on March 4, EST). A rainfall analysis from TRMM's Microwave Imager (TMI) and Precipitation Radar (PR) instruments showed areas of heavy rainfall in several areas, mostly south of the center of circulation. Areas with heavy rain were spotted by the TRMM satellite in the southwestern and eastern quadrants of the storm, and rain was falling at a rate of over 50mm/hr (~2 inches).
Cyclone Irina is now expected to make landfall in extreme northeastern South Africa, south of the Mozambique border late on March 9, but the forecast could again change as Irina has been slowed by various weather factors. There are several parks located near where landfall is currently forecast. Tembe Elephant Park and the Ndumo Game Reserve are located near the Mozambique border and the Isimangaliso Wetland Park is located to the south. These areas are likely to feel the strongest winds from Irina when it makes landfall.
As Irina nears landfall by the end of the week, cold waters stirred up from below the surface are causing sea surface temperatures near the coast to cool, which will reduce any energy going into Irina as it nears the coast for landfall. Once Irina makes landfall, the forecasters at the Joint Typhoon Warning center expect Irina to dissipate quickly. Meanwhile residents of eastern South Africa, Swaziland and southeastern Mozambique can expect more clouds, showers, gusty winds and rough surf in coastal areas as Irina loops back toward land.
Rob Gutro | EurekAlert!
Climate satellite: Tracking methane with robust laser technology
22.06.2017 | Fraunhofer-Gesellschaft
How reliable are shells as climate archives?
21.06.2017 | Leibniz-Zentrum für Marine Tropenforschung (ZMT)
An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.
Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...
Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.
Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...
Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.
As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...
Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.
With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...
Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine
Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...
19.06.2017 | Event News
13.06.2017 | Event News
13.06.2017 | Event News
23.06.2017 | Physics and Astronomy
23.06.2017 | Physics and Astronomy
23.06.2017 | Information Technology