E-Bomb – Direct Energy Warfare

6th Generation Aircraft - Airforces to End the Desire for Pilots

The rules of battle have changed over the entirety of military history. Tools such as technology, strategy, tactics and weapons have been the principal elements determining what kind of rules apply to the battlefield. What can consititute to a sixth generation fighter jets – Thats the question I am asking myself since past week. Although it might be too early to think of these questions, when even planes like JSf, PAK-FA or F-22 are not even fully opertional. The contemporary military rivalry is driven mostly by the ongoing military technical revolution. In particular, the weapons used on the future battlefield will play an important role in military affairs. Which weapons can play a key role in the future? I will try not to be too technical, such that the article is applicable to general public as well, however, I have included the research papers and appropriate links for those intending to explore more about E-Bombs or Electromagnetic Weapon Systems.

Sixth generation jet fighters are currently conceptual and expected to enter service in the United States Air Force and United States Navy in 2025-2030 timeframe. The technological characteristics may include the combination of fifth generation aircraft capabilities with unmanned capibility, unrefueled combat radius greater than 1000 nm and Direct Energy Weapon. It is latter which is a subject of this article. One form of this energy is Electronic Bomb (E-Bomb). This article aim to explore the technical aspects and potential capabilities of this type of bomb, target measurements and its comparison with other form of electromagnectic weaponry.

Research has shown that it is possible to develop such kind of device. Directed Energy research originated with research work done to determine the impact to important military systems operating in harsh electromagnetic environments. One of the most threatening and pervasive of all electromagnetic threats is that due to electromagnetic pulse.

These pulses can burst of electromagnetic radiation that results from an explosion (usually from the detonation of a nuclear weapon) and/or a suddenly fluctuating magnetic field. However, its not only the nuclear weapon who generates these pulses, Non-nuclear electromagnetic pulse (NNEMP) is an electromagnetic pulse generated without use of nuclear weapons. There are a number of devices that can achieve this objective, ranging from a large low-inductance capacitor bank discharged into a single-loop antenna or a microwave generator to an explosively pumped flux compression generator. To achieve the frequency characteristics of the pulse needed for optimal coupling into the target, wave-shaping circuits and/or microwave generators are added between the pulse source and the antenna. A vacuum tube particularly suitable for microwave conversion of high energy pulses is the vircator. These HEMP induced stresses can damage or severely disrupt some electronic systems, which are sensitive to transient disturbance. Significant potential damaging effects can occur at long ranges to virtually all systems located within line-of-sight of the detonation point. Thus it is feasible to say, that NNEMP generators can be carried as a payload of bombs and cruise missiles, allowing construction of electromagnetic bombs with diminished mechanical, thermal and ionizing radiation effects and without the political consequences of deploying nuclear weapons.

The fact that an electromagnetic pulse is produced by a nuclear explosion was known since the earliest days of nuclear weapons testing, but the magnitude of the EMP and the significance of its effects were not realized for some time. As a result of the test, a very short but extremely intense electromagnetic pulse was observed. This pulse propagated away from its source with a decreasing intensity, which is also to be expected according to the theory of electromagnetism.

According to the CBS reports dated March 2003 stated the application of experimental EM Pulse:

The U.S. Air Force hit Iraqi TV with an experimental electromagnetic pulse device called the “E-Bomb” in an attempt to knock it off the air and shut down Saddam Hussein’s propaganda machine. The highly classified bomb created a brief pulse of microwaves powerful enough to fry computers, blind radar, silence radios, trigger crippling power outages and disable the electronic ignitions in vehicles and aircraft. Officially, the Pentagon does not acknowledge the weapon’s existence.

Direct Energy Warfare

Military action involving the use of directed-energy weapons, devices, and countermeasures to either cause direct damage or destruction of enemy equipment, facilities, and personnel, or to determine, exploit, reduce, or prevent hostile use of the electromagnetic spectrum through damage, destruction, and disruption. The defensive part of Electronic Warfare includes the offensive actions such as preventing the enemy’s use of the electromagnetic spectrum through counter measures such as damaging, disrupting, or destructing the enemy’s electromagnetic capability. Such weaponry (DEW) is an evolving addition to the EW.

Characteristics of Direct Energy Weapons

The most common characteristics of the direct energy weapons is that they attack at the Speed of Light. This pose some advantage over conventional weaponry, This helps in defeating targets
such as theater and ballistic missiles before they can deploy defense-saturating sub-munitions. Another advantage of such weapons is that they can be used against multiple targets at the same time. The direct energy weapons are classified into four catagories; High Power Microwave (HPM), Charged Particle Beams (CPB), Neutral Particle Beams (NPB) and High Energy Laser (HEL). It is the latter which is highly potential for military applications (both stratagic and tactical missions). However, for E-Bomb it is HPM is a base. But offcourse when compared to Laser technology, the microwave technology lags in terms of research. HPM – use electromagnetic radiation to deliver heat, mechanical, or electrical energy to a target to cause various, sometimes very subtle, effects. When used against equipment, directed electromagnetic energy weapons can operate similarly to omnidirectional electromagnetic pulse (EMP) devices, by inducing destructive voltage within electronic wiring. The difference is that they are directional and can be focused on a specific target using a parabolic reflector. High-energy radio frequency weapons (HERF) or high-power radio frequency weapons (HPRF) use high intensity radio waves to disrupt electronics. However, High and low power, Pulsed Microwave devices use low-frequency microwave radiation which can be made to closely mimic and interact with normal human brain waves having similar frequencies. Although belong to the same family of technology, the E-Bomb deployment differes from that of HPM.

Potential for Aircraft Operations

Scleher, D. Curtis in Electronic warfare in the information age, has defined the potential of these kind of weapons for Aircraft Operations. DEWs have great potential for aircraft operations since crews can enhance their own survivability in the battlefield, where the aircrafts are susceptible and vulnerable to missile threats, by protecting themselves with electromagnetic shields. In such environment, DEW systems may prevent the aircraft from threats by decreasing the detection and targeting capability of enemy. They may also aid in hit avoidance by deflecting, blinding, or causing the incoming missile to break lock and finally, where necessary, to destroy the missile itself before it reaches its target. An additional approach might be to defeat the fusing system of the incoming missile. However, when deploying these bombs, getting the projectile successfully right is the key, such that useful damage can be produced. Further information about the deployment of these DEWs can be accessed from Electronic warfare in the information age. By this stage one difference between HPM and E-bomb is apparanet, despite belonging to same technological family, and this difference is their deployment. HEMP – High Altitude Electromagnetic Pulse is not a directed energy weapon. The reason why HEMP is defined as an electromagnetic weapon is that it produces similar effects in electromagnetic spectrum and can cause similar impacts on electronic devices. The potential effects of a designed HPM weapon strongly depends on the electromagnetic properties of the target. Since it is difficult to get the required intelligence, the complexity of real systems poses technical difficulties. A typical HPM weapon system basically includes a prime source that generates the intended power, an RF generator, a system that shapes and forms the wave into the intended form, a waveguide through which the generated wave travel, an antenna that propagated the wave, and the control unit that manages all the steps.

AGM-154 Joint Standoff Weapon l

Delivery system considerations for E-bombs are very important. The massed application of such electromagnetic weapons in the opening phase of an electronic battle delivered at the proper instant or location can quickly lead the superiority in the electromagnetic spectrum. This package might mean a major shift from physically lethal weaponry to electronically lethal attacks (via e-bombs) as a preferred mode of operation. Potential platforms for such weapons delivery systems are AGM-154 JSOW (Joint Stand Off Weapon) glidebomb (shown above) and the B-2 bomber (shown below). The attractiveness of glidebombs delivering HPM warheads is that the weapon can be released from outside the effective radius of target air defenses, minimizing the risk to the launch aircraft, which can stay clear of the bomb’s electromagnetic effects.

B2-Bomber refueling

Another delivery method of e-bomb may be the use of UAVs. The technology of UAVs is still developing and partly immature; however, improvements can be expected in the next decade.

The e-bomb targets mission essential electronic systems such as the computers used in data processing systems, communications systems, displays, industrial control applications, including road and rail signaling, and those embedded in military equipment, such as signal processors, electronic flight controls and digital engine control systems. I must point out that when e-bomb outputs are too weak to destroy these systems but strong enough to disrupt their operations, system performance can be degraded. The relation between the altitude (shown below) where the e-bomb is detonated and a representation of the lethality range. Target information (to include location and vulnerability) becomes an important issue.

E-Bomb Footprint: Source <a href="http://cryptome.org/ebomb.htm/">Carlo Kopp</a>

E-Bomb – Science Fiction or a Fact?

Sor, can this hypothetical e-bomb be a significant weapon for the future battlefield? Theoratically, the military advantage obtainable with e-bombs is related mostly to their operational significance. Will future battlefields will be won by the countries that best manage the revolution in military affairs or technological revolution? If latter is the case, then one has to remind himself that technology is not a winner on its own, but it has been, and it will continue to be, a critical enabler. If everything else is equal, the side with better technology will win. Finally, can the country that first develops this new weapon have a significant and exploitable military advantage against other powers? Is is feasible for a nation to invest in this kind of bomb ? – The Debate Continues

As I have mentioned earlier, this piece is not research but infact just collection of some work, to explore the potential of EM technology in modern warfare as well as extending our previous discussion of Electronic Warfare For further reading about the subject I strongly suggest to read the following researches

References
Kopp, C. 1993. A doctrine for the use of electromagnetic pulse bombs. Air Power Studies Centre. Paper No. 15.
Kopp, C. 1996. An introduction to the technical and operational aspects of the electromagnetic bomb. Air Power Studies Centre. Paper No. 50.
Kopp, C. 2006. Directed Energy Weapons-Part 1. Defense Today May/June Publication.
Mazarr, Michael J. 1993. Military Technical Revolution-A Structural Framework. Center for Strategic and International Studies. Washington, D.C.
Scleher, D. Curtis. 1999. Electronic warfare in the information age. Boston: Artech House.

Electronic Warfare Operations – Part I

O divine art of subtlety and secrecy! Through you we learn to be invisible, through you inaudible; and hence hold the enemy’s fate in our hands. – Sun Tzu (The Art of War)

Wedgetail Flares Test

The advant of technology and understanding the control of electronmagnetic specturm (EM) has taken the description of warfare to another level. Modern military forces rely heavily on a variety of complex, high technology, electronic offensive and defensive capabilities. EW is a specialized tool that enhances many air and space functions at multiple levels of conflict. Modern weapons and support systems employ radio, RADAR, infrared, laser, optical and electro-optical technologies. Modern military systems, such as the E-8C joint surveillance, target attack radar system (JSTARS), rely on access to the electromagnetic spectrum to accomplish their missions. So what exactly Electronic Warfare is?

EW is any military action involving the use of the EM spectrum to include directed energy (DE) to control the EM spectrum or to attack an enemy. This is not limited to radio or radar frequencies but includes IR, visible, ultraviolet, and other less used portions of the EM spectrum. As giving air and ground forces a superiority – the application of EW was seen in Operation Desert Storm (Gulf War) – Where self-protection, standoff, and escort jamming, and antiradiation attacks, significantly contributed to the Air Force’s success. Within the information operations (IO) construct, EW is an element of information warfare; more specifically, it is an element of offensive and defensive counterinformation. Electronic Warfare comprises of three main components: Electronic Attack – Electronic Protection – and finally Electronic Warfare Support, all includes the integrated Information Operations (IO).

Key to Electronic Warfare success is the control of Electromagnetic Spectrum Control. This is usually achieved by protecting friendly systems and attacking adversary systems. In reference to above mentioned three components of EW – Electronic Attack, limits adversary use of the electronic spectrum; – Electronic Protection – protects the use of the electronic spectrum for friendly forces, and Electronic Warfare Support – enables the commander’s accurate estimate of the situation in the operational area. All three must be carefully integrated to be effective. Friendly forces must prepare to operate in a nonpermissive EM environment and understand EW’s potential to increase force effectiveness.

Electronic Warfare for Air Forces

Air Force electronic warfare strategy embodies the art and science of employing military assets to improve operations through control of the EM spectrum. An effective EW strategy requires an integrated mix of passive, disruptive, and destructive systems to protect friendly weapon systems, components, and communications-electronics systems from the enemy’s threat systems. During the Gulf War, EF-111 RAVENS were used successfully against Iraqi radars and communications facilities. Conflicts in Vietnam and the Middle East provided deadly reminders of the necessity for effective EW against advanced threats and of the intense effort required to counter these threats. Current technology has given rise to new enemy capabilities, which includes the use of microwave and millimeter wave technologies, lasers, electro-optics, digital signal processing, and programmable and adaptable modes of operation.

Douglas B-66 Destroyer during Vietnam War

During the Vietnam War EB-66 was used against terminal threat radars, surface to air missiles (SAM) and anti aircraft artillery (AAA) as well as used as stand-off jamming platforms. EB-66 modified version of U.S light bomber B-66 Destroyer (shown above). The RB-66C was a specialized electronic reconnaissance and ECM aircraft with an expanded crew of seven, including additional electronics warfare experts. A total of 36 of these aircraft were built with the additional crew members housed in what was the camera/bomb bay of other variants. RB-66C aircraft had distinctive wingtip pods and were used in the vicinity of Cuba during the Cuban Missile Crisis and later over Vietnam. In 1966, these were redesignated EB-66C. After the retirement of B-66, General Dynamics/Grumman EF-111A (shown below) Raven came to play the role. EF-111A Raven was an electronic warfare aircraft designed to replace the obsolete B-66 Destroyer in the United States Air Force. Its crews and maintainers often called it the “Spark-Vark”, a play on the F-111’s “Aardvark” then nickname.

An EF-111A Raven aircraft supplies radar jamming support while enroute to Eglin Air Force Base during the multi-service Exercise SOLID SHIELD '87.

EF-111A achieved initial operational capability, in 1983 EF-111s first saw combat use with the 20th Tactical Fighter Wing at RAF Upper Heyford during Operation El Dorado Canyon in 1986 (retaliatory attack on Libya), Operation Just Cause in 1989. The EF-111A served in Operation Desert Storm in 1991. On 17 January 1991, a USAF EF-111 crew: Captain James Denton and Captain Brent Brandon (“Brandini”) archived an unofficial kill against an Iraqi Dassault Mirage F1, which they managed to maneuver into the ground, making it the only member of the F-111/FB-111/EF-111 family to achieve an aerial victory over another aircraft.

Operational Concepts

The effective application of electronic warfare in support of mission objectives is critical to the ability to find, fix, track, target, engage, and assess the adversary, while denying that adversary the same ability. Planners, operators, acquisition specialists, and others involved with Air Force EW must understand the technological advances and proliferation of threat systems in order to enable friendly use of the EM spectrum. To control is to dominate the EM spectrum, directly or indirectly, so that friendly forces may exploit or attack the adversary and protect themselves from exploitation or attack. Electronic warfare has offensive and defensive aspects that work in a “movecountermove” fashion. To exploit is to use the electromagnetic spectrum to the advantage of friendly forces. Friendly forces can use detection, denial, disruption, deception, and destruction in varying degrees to impede the adversary’s decision loop. For instance, one may use electromagnetic deception to convey misleading information to an enemy or use an enemy’s electromagnetic emissions to locate and identify the enemy. To enhance is to use EW as a force multiplier. Careful integration of EW into air and space operations will detect, deny, disrupt, deceive, or destroy enemy forces in varying degrees to enhance overall mission effectiveness. Through proper control and exploitation of the EM spectrum, EW functions as a force multiplier and improves the likelihood of mission success.

Billion Dollar Market For Electronic Warfare

Forecast International’s “The Market for Electronic Warfare Systems” projects an estimated $28.4 billion will be spent over the next 10 years on the development and production of the major EW systems. Some 44,807 units of leading Electronic Countermeasures (ECM), Radar Warning Receivers (RWRs), Electronic Support Measures (ESM), and other EW systems that make up this analysis will be produced. The top-ranked EW producers cited in the analysis (out of a total of 22 companies considered) are Northrop Grumman, BAE Systems, Raytheon, ITT, and Lockheed Martin. While production of leading missile countermeasures systems has helped position some of these companies at the top of the ranking, others are leading the development of all-important, next-generation technology. It is important to add that today’s EW market leaders are firmly established because of their ability to provide much-needed EW systems for immediate deployment to the battlefield. To cite just one example, despite some defense budget tightening, the Pentagon is expected to spend over $560 million through FY13 on procurement of Northrop Grumman’s Large Aircraft Infrared Countermeasures (LAIRCM) system for various Air Force aircraft. The service has declared that its long-range desire is to equip a total of 444 aircraft with the system. The market for systems to defeat improvised explosive devices (IEDs) will also warrant close monitoring in the years ahead. With the recent surge of U.S. troops into Afghanistan, there has also been an increase in the occurrence of IED attacks. To counter these attacks, a competition is currently under way for development of a Counter Radio-Controlled Improvised Explosive Device (RCIED) Electronic Warfare (CREW) 3.3 system of systems. The U.S. Naval Sea Systems Command in October 2009 awarded firm-fixed-price contracts to two companies for CREW 3.3 System of Systems development. ITT Force Protection Systems was awarded $16 million, while Northrop Grumman Space and Mission Systems, Network Communication Systems was awarded $24.3 million. International ventures will also have a significant impact on the EW market through the new decade. The primary platform for ITT’s ALQ-214 Radio Frequency Countermeasures (RFCM) system is the U.S. Navy’s F/A-18E/F Super Hornet. Through its association with the jet fighter, a potentially growing export market for the ALQ-214 has begun to emerge. For example, the system will equip the F/A-18Fs purchased by Australia a stopgap measure until its F-35 fleet is ready for service.

I will continue the implementation and integration of three major components of Electronic Warfare in my next post. Please do check back

Pakistan Floods, Do We need to know the Science

Please note that this article is not a final report or concluding research on the subject, but instead combination of possible factors that may have contributed to the severe July 2010 flooding in Pakistan. All scientific statements contains a valid references. Hence, the article must not be confused with the actual findings from the Meteorological Department findings. In mid August, many respected scientifc sources such as New Sicentist, Scientific American, NASA, or BBC discussed this issue in depth lying down some possibilities as well as satellite results. I have mentioned some of the results from these studies, with my comments.I will surely update the post and try to put some authenticate results with the permission of the owners once I have the access to them.

In late July 2010, flooding caused by heavy monsoon rains began across several regions of Pakistan. According to the Associated Press, the floods have affected about one-fifth of this country of more than 170 million. Between July 28 and 29, up to 400 millimeters (16 inches) of rain fell from these storm cells, triggering flooding along the Indus and Kabul Rivers. Storms with similar structures to this one have become common this summer as tropical monsoon moisture, coupled with a strengthening La Nina (which has different effects around the world), dominate this region’s weather patterns.

[Source: NASA]

The above figures are obtained by NASA’s CloudSat satellite. As seen in the top half of the bottom image, CloudSat classified the majority of the clouds present at the time as deep convective (cumulonimbus) clouds, which are typical of thunderstorms. The bottom half of the lower image shows the 3-D vertical structure of the storm along the satellite’s flight path, revealing its heavy precipitation. As CloudSat’s Cloud Profiling Radar passed over the area of heaviest precipitation, its signal thinned significantly. By the middle of the image, the ground echo (horizontal red line), which represents the topography of the area, completely disappears. The thinning of the radar’s signal occurs because larger-sized particles and heavy rains decrease radar reflectivity and become indistinguishable to the radar. As the satellite continued traveling north, rainfall rates decreased and the signal increased, allowing the ground echo (topography) to once again become visible, at the far right of the image. CloudSat measured the height of the clouds along the radar’s flight path at around 15 kilometers (9.3 miles) in the areas of deepest convection.

Storms with similar structure to this one have become common this summer as tropical monsoon moisture, coupled with a strengthening La Nina, dominate this region’s weather patterns.

BBC Science department also presented results from SMOS satellite. SMOS satellite has revealed the results based on the observation made from 17th July to 4th August. Four snapshots (obtained on courtesy of CESBIO/BBC) reveals the damage done, which off-course is much more severe now.

Satellite data is frequently used in the relief response to major disasters, and in the case of Pakistan the world’s satellite fleets were mobilised on 2 August to provide space-borne information under the International Charter [on] Space and Disasters. The severity in the floods is apparent from the above set of figures, showing the ground getting progressively wetter, highlighted by transition from yellow/orange to blue/gray region.

Dr Claire Gruhier, France based Smos researcher, told BBC News the results were preliminary: “What we show is not the flood area; what we show is the water content in the soil. So, it is not exactly the same information. But our maps are very consistent with the flood-affected areas in Pakistan revealed by other satellites.” According to the sources, the SMOS team is confident that once the data obtained is validated and algorithms fine tunes, the team will be able to infer also the extent of actual floods.

SMOS – Soil Moisture and Ocean Salinity (SMOS) mission

ESA’s project for Soil Moisture and Ocean Salinity (SMOS) mission, which has been designed to to observe soil moisture over the earth’s landmasses and salinity over oceans. These analysis are important for hydrological studies and to gain better understanding of ocean circulation patterns. Moreover, the mission will also contribute to further understanding of Earth’s water cycle. Launched on 2 November 2009, SMOS is the second Earth Explorer Opportunity mission to be developed as part of ESA’s Living Planet Programme.

This data is particularly useful for extreme weather forecast predictions as well as to pick up seasonal climate changes within the defined region. An important aspect of this mission is that it will demonstrate a new measuring technique by adopting a completely different approach in the field of observing the Earth from space. A novel instrument has been developed that is capable of observing both soil moisture and ocean salinity by capturing images of emitted microwave radiation around the frequency of 1.4 GHz (L-band). SMOS will carry the first-ever, polar-orbiting, space-borne, 2-D interferometric radiometer.

Why is it important to observe soil moisture ?

Simply because it plays an important role in the global water cycle. However, in-situ measurements of soil moisture are sparse but, if we are to better our understanding of the water cycle so that the forecasting of climate, weather and extreme-events can improved, more data are urgently required.The same is true for data on ocean salinity. There are few historical measurement data, and only a small fraction of the ocean is currently sampled on any regular basis. Salinity and temperature determine the density of seawater, and in turn density is an important factor driving the currents in our oceans. Ocean circulation plays a crucial role in moderating the climate by, for example, transporting heat from the Equator to the poles. Ocean salinity is therefore one of the key variables for monitoring and modelling ocean circulation.

Based on Scientific American Observation, Although Global Warming or adverse climate changes can be blamed for the floods in Pakistan, but some sources believe that A major factor that led to the massive flooding is illegal logging in the northwest province of Khyber-Pakhtunkhwa. In forestry terms, illegal logging is simply a timber theft. Illegal logging is a pervasive problem, causing enormous damage not only to forests, but also to local communities. This contributes to deforestation, and by extension global warming. These illegal activities undermine responsible forest management, encourage corruption and tax evasion and reduce the income of the producer countries, further limiting the resources producer countries can invest in sustainable development.

This argument further justified by Jamshed Ali, Secretary-General of Sarhad Awami Forestry Ittehad (SAFI),an organisation meant to protect forests in the province, Ali, said in parts of Malakand district more than 70 per cent of forests had been felled by a well-connected “timber mafia” that was difficult to stop. The blame was indeed put on Talibans by Mr Ali.

Human Failure Again ?

According to the article published Scientific American, more statements followed by many respected sources of Pakistan, Over-grazing by livestock — common in rural Pakistan — can also remove layers of topsoil and stunt plant growth, reducing the soil’s ability to hold water, said Asad Jarwar Qureshi of the International Water Management Institute. And more, Abdul Qadir Rafiq of the United Nations Development Programme says without vital topsoil, flash-flooding in northern, mountainous areas can result, sending silt downstream which then reduces the amount of water the river channel can hold. “We need to clear the river channels of silt every four to five years and stop people living within a kilometre of the river channel. There are irrigation channels built using techniques from the 18th century. We need to react to the present-day,” Qureshi said.

Off-course, all of the above statements, can be further challenged by blaming everything on extreme weather patterns, which has always played its part. But the nation has to realize, a potential threat and must learn to act in her favor. But it must be evident that, though there exist the chances of illegal logging or overgrazing in the corrupt society like this exists, particularly In the militant-infested Swat region, as Secretary-General of Sarhad Awami Forestry Ittehad (SAFI) has said, but these are not the only reasons. To my opinion, the Climate Change does play an important role with an appropriate river management techniques, which unfortunately have always been ignored.

Source: Climate Change, Human Failing behind Pakistan Floods, By Rebecca Conway (Scientific American Aug 31, 2010)

Combination of strong polar jet stream with usual monsoon in Pakistan, to cause unusually intense flooding.
Then, having taken up such an unusual position, the jet stream just sat there, frozen in place. The weather systems causing the heatwave and the torrential rains remained in place for more than a month, continuing to contribute to the increasingly disastrous conditions. The reason for such unusual condition aren’t clear yet, but it is believed that human-induced climate change has increased the certainty of severe heat waves.

[Source: Weird Science]

Based on the Pakistan’s Meteorological Dept, it was suggest earlier July (in a usual monsoon update) that strong tropospheric winds are expected. Based on the observations made in June 2010, due to high sea-land temperature contrast the development of some mid-tropospheric circulations were likely (particularly over Sindh region). Moreover, in same observation report prediction of a very heavy rainfall events were made over northern region of the country. This is due the interactions of westerly-easterly waves (so called jet stream). The report was made with 80% of confidence level, which suggests that alarm was made well in advance. But still no precautions were actioned by the government. Whether this is lack of communication or laziness of the government, the damage has been done and its seriousness is clear enough.

What are Jet streams and why are they so important ?

In very simple words, the jet stream is a current of fast moving air found in the upper levels of the atmosphere (troposphere 10-16 km) above earth surface. The position of this upper-level jet stream denotes the location of the strongest surface temperature contrast

Usually in summer, these waves are weaker, primarily because of less dramatic surface temperature changes. These waves and their strength is evident in figure above, with jet streaks, shown in red. Latter are localized regions of very fast winds embedded within the jet stream. Sometimes these local wind maxima reach speeds in excess of 160 knots. As air enters a jet streak, it speeds up. When it leaves a jet streak, it slows down. These accelerations and decelerations, coupled with the curvature of the jet stream and strong wind shears, cause air to pile up in some areas (convergence) and spread out (divergence) in others. These regions of divergence and convergence have a significant influence on surface pressure features.

Bypassing complex scientific principles, a simple physics can tell us a much about what we can expect. Generally warmer temperatures imply more extremes high temperatures. Second, warmer air holds more moisture, meaning that we can expect higher peak rainfall rate and daily totals, locally and regionally, from both convection (thunderstorms) and larger-scale weather systems, where air is forced to rise and cool in clouds, condensing its water vapour and creating rain.

Moreover, Possible changes in regional weather patterns will mean that an individual region may see substantially larger changes (both negative and positive) than those implied by the globally averaged change. As I have mentioned earlier, that saying that current flooding is purely due to climate change is difficult. Though, by knowing the Arabian sea temperature, the above argument can either be accepted or rejected. This means that if the sea temperature is cool enough, than above warm air holding water argument can be eliminated, but that may not be the case.

It is the position of the Jet stream, Low pressure weather, depressions (cause heavy rain), duration of this weather is also concern, Why these waves remain there, don’t know ? Many believed linked with La Nina

La Nina occurs when cool water surges up from the bottom of the ocean (Pacific). The water cools the air above it, setting off a series of changes in the Earth’s atmospheric circulation.

Frozen jet stream links Pakistan floods

According to meteorologists monitoring the atmosphere above the northern hemisphere, unusual holding patterns in the jet stream are to blame. As a result, weather systems sat still.Temperatures rocketed and rainfall reached extremes.The notice in the usual pattern of these waves have been observed, the waves normally shift east, dragging weather systems along with it. But in mid-July they ground to a halt, say Mike Blackburn of the University of Reading, UK.

Stationary patterns in the jet stream are called “blocking events”. They are the consequence of strong Rossby waves, which push westward against the flow of the jet stream. They are normally overpowered by the jet stream’s eastward flow, but they can match it if they get strong enough.A static jet stream freezes in place the weather systems that sit inside the peaks and troughs of its meanders. Warm air to the south of the jet stream gets sucked north into the “peaks”. The “troughs” on the other hand, draw in cold, low-pressure air from the north. Normally, these systems are constantly on the move – but not during a blocking event.And so it was that Pakistan fell victim to torrents of rain. The blocking event coincided with the summer monsoon, bringing down additional rain on the mountains to the north of the country.

According to the source [OptimumPopulation.Org];

Similarly, as the static jet stream snaked north over Russia, it pulled in a constant stream of hot air from Africa. The resulting heatwave is responsible for extensive drought and nearly 800 wildfires at the latest count. The same effect is probably responsible for the heatwave in Japan, which killed over 60 people in late July. At the same time, the blocking event put an end to unusually warm weather in western Europe.

So what is the root cause of all of this? Meteorologists are unsure. Climate change models predict that rising greenhouse gas concentrations in the atmosphere will drive up the number of extreme heat events. Whether this is because greenhouse gas concentrations are linked to blocking events or because of some other mechanism entirely is impossible to say. Gerald Meehl of the National Center for Atmospheric Research in Boulder, Colorado – who has done much of this modelling himself – points out that the resolution in climate models is too low to reproduce atmospheric patterns like blocking events. So they cannot say anything about whether or not their frequency will change.

In the next post I will comment on the above points, and try to come up with the final possible points which may have led to this disaster. Many advanced nations, have developed the Disaster Management TEchniques, not only management but prevention as well. This was evident in 2007/08 UK’s flooding, which was recorded to be one of the worst in nation’s history. Of about 17,000 families forced from their homes in England, about 1,000 were still living upstairs or in temporary accommodation earlier this month. Although it is not possible to eliminate the risk of flooding completely, but it is indeed possible to learn from the mistakes and save as many lives as possible. From Pakistan’s recent experience it is evident that necessary measures has to be taken by the Government but also as citizens of Pakistan, since it is us, who are constantly in touch with the Environment.

[Sources:]
http://www.optimumpopulation.org/blog/?p=2711
http://www.wired.co.uk/news/archive/2010-08/16/jet-stream-kink