The 9/11 Operation: A Summary – PORT AUTHORITY OF NEW YORK CONTRACTED REQUESTED BEFORE SEPT 11TH 2001 — FINNISH MUNITIONS EXPERT DOCUMENTATION OF WTC AND CUTTER CHARGED DEMOLITION PLANS AND SCHEMATICS !! DR A. TRUE OTT PhD ND
The 9/11 Operation: A SummaryThe 9/11 Operation: A SummaryThe 9/11 operation consisted of the following activities:Military exercises by the North American Aerospace Defense Command (NORAD) with 22 imaginarily hijacked planes on 9/11/2001, before and simultaneously with the “real” hijackings. Some of the defense interceptors flew to Alaska, as far as possible from the cities that were being attacked. All FAA Flight Termination Systems (FTS) were deactivated so that no “false groundings” of commercial planes would occur. The operation involved the “hijackings”of four civilian aircraft, then substituting them with remote-controlled USAF aircraft or “drones”. It is certain that an operation this complex and sophisticated (even in the preparations of the demolition charges at the WTC) is not left to be handled by Arab lackeys armed only with carpeting knives. Plissken-Valentine, FTS by SPC or Pearl are well-documented available technologies on how the aircraft/attack portion of the operation was performed. Since the part of airplanes hijacked and flown into buildings was critical to the real aims of the operation there must have been a couple of reserve planes for the USAF – Boeing 767’s and the Global Hawk. Alternatively, the Boeing 757 shot down in Pennsylvania might well have been a remotecontrolled reserve plane utilized because of the NORAD exercises.The booking of seats on certain pre-ordained flights was artificially kept low; those coastto-coast flights were booked by 20% instead of the usual 75% in order to minimize deaths, which could cause problems if “highly connected” individuals were wantonly sacrificed. If the flights were real, the passengers on them had to die (or at least disappear). Two of the flights were probably nothing but fictitious, real only on radar screens, which minimized the amount of passengers to be murdered.There was indeed placing of well executed put options with airline stocks and with specific re-assurance companies (American Airlines, United Airlines, Allianz, Munchener Re, Schweizer Re, AXA, et.al…). Furthermore, the assurance values of the WTC were doubled in July 2001, at the same time the MOSSAD’s offices at the WTC were vacated. Bush’s Carlyle Group members were beneficiaries of these options –a very vital set of “smoking gun clues” that were completely ignored or conveniently forgotten by official “investigators” in the days, weeks, and months following thejoint CIA/Mossad operation.The camouflaging of six remote-controlled aircraft in order to make them look likeBoeing 767’s or 757’s. The four planes probably were 2x USAF 767 tankers, a Global Hawk used to hit the Pentagon and a “real”757 shot out of the air in Pennsylvania.False tracks leading to “terrorists”using young Moslem-looking persons on CIA payroll, who take aviation classes in Southern USA and party at night clubs, were created.Demolition preparations of the wing of the Pentagon that was under reparation. This was designed to collapse a horseshoe-shaped area of the building, which would seem to be caused by the crash of a Boeing 757 instead of the Global Hawk attack. This partly failed. There is photographic evidence of a small plane before the actual collapse of the wing of the Pentagon. The structures did not collapse until firefighters sprayed lots of water on the ceiling of the building.Sophisticated demolition charge preparations of the WTC towers and WTC 7 to make them collapse completely and look to the untrained, gullible eye as if the buildings collapsed solely from the effects of gravity and burning fuel. Also the positioning of an electronic homing device in the towers and in the Pentagon in order to ensure the accurate hits of the remote-controlled aircraft was needed. Extra napalm was supplied for dramatizing the effects of hits of airliners. The WTC buildings would have been demolished in the exact same way completely with or without the airplanes hitting.Ordering, preparing and transportation of the charges for the demolition of the WTC had to be done, no small feat to say the least. Solely for the steel pillars of the outer circle 40 x 240 charges were needed, let’s say 10,000 thermite cutting charges each weighing 50 lbs for each tower. For WTC 7 at least 4000 charges were needed. Also at least one small thermonuclear hydrogen bomb for each of these three buildings was prepared. (Did the 9/11 “investigators” check intoany demolition charge purchases over the prior year?)Identifying critical need targets for the conspiracy in the WTC towers various offices. For example, there was a lot of evidence being gathered of world-wide economic crimes by Neocon Zionists. The FBI’s international divisionwas located in WTC 1 in the floors from 22 to 24. (One case being investigated was the case against Mobil Oil and James Giffen on illegal oil swaps between Iran and Kazakhstan brokered by Mobil Oil and Carlyle Group in Texas; also the ongoing evidence in the investigation of gold price fixing stemming from charges pending to go to Federal Grand Jury seeking indictments against Alan Greenspan, JP Morgan & Company, Rothschild & Sons, and Goldman Sachs.) The CIA maintained a large operations office in WTC 7. It is possible that some targets were attacked because of the unique opportunity exploitable where the human bodies and all evidence of the crimes automatically disappeared when a hydrogen bomb exploded. Explosions heard from the towers before the commencing of the “collapse” may have been related to these attacks. There is a reason for the huge explosion in the customs building, as well.THE DEMOLITION OPERATION OF THE WTC TOWERS1) Calculate the correct size and the dimensions of suitable cutting charges and then order 24,000 pieces. Must also order fitting detonators (custom detonators had to be manufactured). Fitting detonators usually already exist in stores of military forces (as well as the CIA’s “Covert Labs”). Time of delivery is several months in any case. All detonators must be equipped with some kind of safety mechanism, which will be removed by a radio signal at the final moment.2) After procurement, the cutting charges are installed in selected vacant rooms and elevator/maintenance shafts. Some of these rooms also served as temporary storages for charges needed elsewhere. After the charges are set, the office is renovated and circulated to the clients in the WTC. One man continuously assembles maybe 5 cutting charges per hour. With 10 assemblers 350 charges are assembled and installed a day. Maybe about 20 people more were needed (5 of them know what is going on, 15 do not). For the installation of the charges this operation takes at least four months with 30 men. Considering step 1), six months are probably needed. The amount of personnel could not have been increased, but probably decreased, if more time was available.3) To some of the chosen office complexes, no one had access. That is why on the weekend on 9/8/2001 and 9/9/2001 it is announced, that floors up from the 40th floor are being equipped with new cables and no “normal employee” hadaccess to the working area there. The installations of explosives are completed and at the same time (at least in the charged areas) listening devices are set to find out a possible premature discovery of the plan. If someone finds charges the guards are soon on the scene and will deal with the situation in one way or another.4) One completes the area of secret service in WTC 7 so that its demolition operation can be carried out. A military flight beacon is placed there (planes are homing to it from far away). Remote controls for air planes and radio transmitters to be capable of blowing up at least one third of the cutting charges are placed. At this location, the ability to eavesdrop any area of the WTC, for example by a laser beam, aimed to a selected window, probably already existed.5) A radio beacon helping the final approach is placed in targeted offices in the WTC towers. Close to these, remote controlled napalm explosives are placed as well, in order to draw the interest from the planes to fires. The higher in the towers the planes are targeted, the less death would result. (Real terrorists would do exactly the opposite.) Evacuation from lower floors should be possible through the staircases. The target is to create a new reason for odd wars and fascistic laws, not to kill as many Americans as possible. “A new Pearl Harbor”, meaning the death of about 3000 unsuspecting, innocent citizens is the desired loss of lives.6) The attack plans are made so that they can be executed during the chaos, for example in the offices of the investigations of the economic crimes by the FBI. (The attackers had already placed or infiltrated their own men in these facilities.) Also in WTC 6 (customs) either a small nuke or a very strong bomb is also detonated (which one, depends on whether there was melted steel ponds in the cellar of WTC 6.) An explosion, of course, hides the loss of any supplies. (A nuclear explosion covers up murders, as well.)7) In the morning of 9/11 the operations are performed after a timetable in which seconds are important. From the command post facilities the actions in towers are monitored. To hide the true nature of the operation, there was probably an agent on call in both towers, who could silence the people finding out too much. (The agent probably did not know what was going to happen.)It is highly unlikely that the people who knew about the demolition charges in the WTC, or those who installed the remote controls of the aircraft or did some camouflage paintings for drones are still are alive and capable of telling about their acts, which changed the world.8) The mini-nukes are transported to the basement floors in elevators. After that the elevators are locked down, guarded and monitored – no service repairman will be allowed near these elevators. The thermonuclear device used in WTC 7 was different, its yield was set lower and it was directed in a way better suitable for that building.9) The explosions have been timed so that 99.9% of people around will look at the top of towers, and perhaps two seconds later the small thermonuclear bomb is exploded in the cellar of the south tower, and again two seconds later another very powerful charge in the WTC 6 customs building while nobody is looking that way. There are also the continuous explosions of the thousands of cutting charges tearing the south tower down to coincide with the speed of gravity-driven free fall.10) The demolition of either of the WTC towers took at least half a year to prepare, including installation of 10,000 cutting charges and the delivery of a thermonuclear device at the last moment. The demolition of those ultra strong steel pillars in the central core using cutting charges only is not possible without waking up unwanted attention. These charges must be in touch with the steel pillars, and there is not enough enclosed space in the central core itself to hide these biggest possible charges.11) The demolition operation is finished by destroying WTC 7 using a nuke and completely destroying the op center with its equipment. Concrete evidence like the military flight beacon and the remote control devices for cutting charges and napalm as well as the recordings of eavesdropping devices regarding events within the towers vaporize and vanish without a trace.SIDE MARKINGSMost of the media is controlled by people related to the attack and tell misleading stories only, as if crushing of the airliners or a weak fire could have caused the “collapse”of the towers. The true attackers are the ones with strong and vigorous broadcasting around their false version of the events which is very different to what really happened.No single “mainstream”newspaper, magazine nor any national TV channel in the western nations has taken a critical, questioning view on the so-called “official truth”, i.e. the planes collision and resulting fires caused the WTC towers to collapse. The destruction of WTC 7, which has no explanation at all (not hit by jets, or fiery debris), is bypassed totally and completely without any comments. A huge bomb of some sort, detonated in WTC 6 is also bypassed as a “non-existing event”.Some things, like the sharply-drawn pictures of the closest seismographs may have been falsified. A Specialist in demolitions, V. Romero, may have been forced to change his original statement. The hoax is completed by Osama Bin Laden, who as a CIA agent “confesses”to have ordered the airliner strikes. The Bin Laden hoax and the suicidal Arabs construct a net of lies that fools the vast majority of mankind.Laymen have no experience in observing differences in collapses, controlled demolitions and underground nuclear demolitions. Even the destruction of heavy steel constructions or typical fire damage are far away from their field of experience. These towers were built and professionally engineered to take the impacts of hitting Boeing 707’s, comparable to Boeing 767’s, taking into account the fires caused by the burning aviation fuel. In fact, the buildings did in fact survive all of that. They stood firm for nearly an hour, until they were demolished. (NYFD personnel are trained on the structuralstabilities of the cities’ high rise buildings. If there was a clear and present danger of “collapse” it is unlikely the firemen would have been ordered into the building.)The knowledge of relevant advances regarding weapon technology is even rarer. Many of those who are up to date are bound by strict commitment of loyalty and secrecy, that is strictly enforced. In some cases, they get executed for talking (an “accident”occurs).The author of this text feels it is his duty to spread his advanced knowledge in explosives from a military point of view via public discussion as it is obvious that the public is lacking this information. The events observed around 9/11 cannot be rationally explained any other way.The photographs attached in this non-profit distribution are for securing volatile, important evidence on 9/11 for discussion and education. Author hereby grants full permission to reproduce the drawing ‘The Bombs in the WTC’ and his writings. You are encouraged to mail, publish and mass produce these documents or your enhanced versions of them. The Bombs in the WTC(Schematic Provided by Anonymous “Insider”)The thermonuclear bomb used was a “pure”hydrogen bomb; no uranium or plutonium was used at all. The basic nuclear reaction is Deuterium + Tritium > Alpha + n. The ignition of this is the tricky part, either a powerful beam array or antimatter detonator was likely used (a very certain way to get the necessary effect of directed energy in order not to level the adjacent blocks of high-rise buildings as well).The Development of Bomb Technology Related to the 9/11 OperationThese outlines of developments in military bomb technology have been written to give the layman some idea, why bomb technology has developed into what it is.A hollow charge: a small charge designed to make a hole in armor plate was invented in Switzerland in 1937. A cutting charge, used in the WTC in tens of thousands of pieces, was an evolutionary model of the principles of a hollow charge from 1950’s.A Claymore threw steel balls towards the enemy, but was otherwise harmless even from 5 meters distance, was developed in the USA approximately in 1960.A flank mine is able to direct a narrow pressure wave through AFV flanks from a distance of 20 meters and was developed in Finland around 1970. Due to efficiency needs, a growing part of military explosives deploy improvements utilizing directed explosion energy.By controlling several layers of the explosion fronts the size of a nuclear bomb has been minimized during the 1960’s (fission forcing implosion). After that, the control of explosion force in nuclear explosions was developed. Too strong an explosion is sometimes unusable and undesirable, for example when the enemy have broken the front and advanced too close to friendly cities.While looking for a bomb with a small size and a strong effect, a 100% pure hydrogen bomb was an obvious solution. When no atomic device is needed for igniting, the size of the hydrogen bomb gets even smaller and the yield (effect) can be set within a wide range, for example between from 1 to 100. This new technology was perfected in the 1980’s, as well as the neutron bomb, which kills only living things while it leaves most inert material untouched.The former Soviet Union is said to have had more than 500 command centers durable for repelling a small nuke attack. That led into the developing of different types of bunker buster explosives. A working solution the U.S. military developed is a nuclear missile that directs 96% of its yield into a thin, all penetrating heat+blast wave in a concentrated, specific direction, tunneling hundreds of meters downwards into and melting solid rock. This type of a hydrogen bomb was developed and perfected sometime in the early 1990’s. Nowadays, both the yield and the direction of the destructive force of a small tactical hydrogen bomb can be somewhat controlled. The amount of fusion-able materials control the yield (effect) and the shape of the charge as well as the initiation arrangements impress the direction of the explosion wave.Observations Suggesting the Use of Small Hydrogen Bombs2) Very energetic dust (radiating heat) after the explosions. (Demolition charges using thermite or other demolition explosives would produce white clouds of dust, which would not move much, and a gravity-driven collapse would produce muchless and more coarse dust. Only a thermo-nuke would provide the kinetic energy to produce such “hot-to-the-touch” flour-fine dust particles.)3) Variable brown shades of color was seen in the air –these “brown clouds”are typically produced by nuclear reactions of a thermonuclear device. The reactions use gamma radiation caused by free neutrons, N2, O2, H2O > nitrid acid, NO2,NO3 which in turn provide brown colored clouds after detonation. These clouds soon get their usual white color after some minutes as the heat and fast movement of the clouds cease.Note: many of the pictures taken regarding the WTC Towers and the clouds seem to have been developed too artificially blue in color, replacing the shades of brown seen and remembered by eyewitnesses. (This may have been an attempt to suppress the evidence.) Also there was supposed to be 200,000+ gallons of water on the roof of each tower –this water was spilled into stairwells etc, but was later all converted into water vapor reducing the brown color. location F C nameA 1341 727 WTC7B 1034 557 WTC7C 1161 627 WTC1D 963 517 WTC1E 819 437 WTC3F 801 427 WTC2G 1377 747 WTC2H 1017 547 WTC4
Thermal Survey of the WTC 9/16/2001 (NASA /US Geological Survey). Despite the fire department efforts to cool the rubble, molten metals would still be extremely hot (up to 1377 degrees F) in some sites 5 days after the incident. Burning jet fuel remnants (especially diesel fuel in Location A –Bldg. 7) would never be this “hot” after 5 days. However, thermo-nuke residue remains “hot” for many days. Red-hot, semi-molten metal pulled from the base of WTC building 7 in late October, 6 full weeks after it collapsed, (no plane collided with it, and it was still standing unscathed hours after the twin towers had already collapsed). WTC 7 on afternoon of 9-11-01. WTC 7 is the tallsky-scraper in the back-ground, right. Seen from WTC 1 area. The “Shock and Awe” of the Nation over the towers’collapse likely precluded rational questioning about WTC 7.5) Elevated values of tritium were recorded in locations A-H, but not found anywhere else in New York. The University of California found elevated values on 9/13/2001 and 9/21/2001 but only within the boundaries of the WTC. They found the elevated levels of tritium “harmless” to human health. Again, in a pure hydrogen bomb isotopes of hydrogen are fused (D + T > n + a + 17.6 MeV).6) An Electro-Magnetic Pulse (EMP-type) phenomenon blacked out GSM phones, cell phones, fax machines and rescue personnel’s radiosat the exact moment when the first (southern) tower started to “fall down”, i.e. at the exact moment when a small thermonuclear bomb was detonated. This is why rescuing firefighters were not warned to evacuate –their radios had mysteriously quit working. A strangely eerie afterglow was seen in the late phase of the “collapse” of both of the towers. 8) In the basement level, out of all the 47 ultra strong steel pillars, the steel was melted completely at the length of more than 20 meters (approx. 65 ft). Even cars were melted and burned in the basement level at “ground zero”. The pillars were far too thick for such massive pulverization via thermite, which some have suggested. An explosion of a thermonuclear bomb, on the other hand, explains the phenomenon well. (How is it even remotely possible for rational people to accept the “official story”that burning jet fuel in the upper portion of the tower melted steel columns and even cars in the basement level?)9) Steel columns and pillars were ejected from the outer layers of the building. In the beginning of the so-called collapse, no such natural, gravitational-based energy exists that could throw steel pillars outwards from 60 to 175 meters (approx. from 170 to 574 ft.) away from the trunk of the building. Not even the most powerful cutting charges can do that. However, once again, a blast wave from a small hydrogen bomb is very capable of doing just that.How the Towers of the World Trade Center collapsedThe airplanes did not affect the destruction of towers; they were needed instead to give the ruling neocons an excuse for instigating their odd Orwellian wars, while at the same time turning the USA into a police nation, much like the German Third Reich, to some extent. The towers took and withstood the impacts of crushing Boeing 767’s. The towers were originally built and engineered to take impacts of Boeing 707’s, which are approximately of the same size and were widely used in the 1970’s.Fires that burned from the fuel in the planes were too short-lasting and weak to be able to severely damage the structural integrity of the skyscrapers. Even in the most extreme situation, the heat from a kerosene fire cannot threaten the durability of a steel trunk. The temperature of carbon-based fires reach only 825 °C (approx. 1517 °F) in “ideal” enclosed furnace conditions, steel weakens at 800°C (approx. 1470 °F) but does not actually become molten until a temperature of 1585 °C (approx. 2890 °F) is reached. In the skyscrapers of the WTC the environment simply was not at all “ideal”as there were far too many steel columns which were purposefully engineered to channel heat away from the burning area. WTC 1 burned for 102 minutes and WTC 2 for 56 minutes only. A fire burning much longer, from 10 to 20 hours in a purely ideal environment could theoretically slowly increase the burning temperature to perhaps 1100 °C (approx. 2010 °F). But that is only if there is more fuel and gasses to burn; such a fire will damage concrete and irons, but not severely damage or “melt” heavy steel construction beams and girders. Again, a fire ignited by a finite amount of jet fuel would simply not “melt” steel columns. For example, in mid-February in Madrid, Spain, the Windsor Tower (see above) burned for over 20 hours, which created a fire many times hotter and more destructive to metal than that in the WTC, but even the damage to the Windsor Tower caused by the very strong and long-enduring fire were comparatively minimal and limited to the upper floors –and of course, it did not melt the hotel’s steel girders. Like the Windsor Towers, if either of the WTC towers had started to collapse because of fires the collapse would have been limited to only a few of the floors and then stopped as the fire became contained.The complete and total impossibility of a “gravitational collapse”is closer seen in other documents. A gravitational collapse would produce large pieces of rubble, and a non-symmetrical toppling of the structure. Furthermore, “gravitational collapse” simply does not explain the pulverization of fine dust from concrete, the vast amounts of micron-fine “powdered”dust that was hot to the touch, and pieces of steel ejected outwards over 500 feet.Destruction of the towers by explosions is furthermore clear according to the photographs and reports of the eye witnesses. In the picture below, a range of cutting charges have just exploded in the down left sector and a typical white cloud is formed outwards from the wall. Down right, explosions are seen as well. Even a detonation flame is seen, many stories below the point of impact. In video tapes taken of the planned demolition of the WTC, more explosions of these cutting charges can clearly be seen. The explosions advance quickly, with a gap of a couple of floors, cutting the strong steel pillars in the outer wall. The explosions are skillfully timed so that it appears that the tower collapses occur in the same timing as in a gravitational collapse. The explosions are not completely synchronized in timing, probably a few charges are triggered by radio, and other charges explode out of the impulses of one of these charges (infrared, pressure wave).More challenging problems to the demolition men, however, were the reinforced steel central cores of the buildings and the 47 steel pillars more robust even than the ones on the outer rounds. The pillars of the central cores were made of steel 100 + 100 mm thick, much thicker than the side armors of a battle tank. Cutting those, even with explosives, is extremely difficult. One would need to surround the whole pillars, every single pillar on every floor blasted with powerful cutting charges. These charges would have needed to be placed in such a way that the inhabitants of the skyscrapers could not notice these preparations.As seen in the following pictures, the cores of the towers were not destroyed by thousands of powerful cutting charges of thermite as were the surrounding beams, but rather by a modern thermonuclear explosive, a small hydrogen bomb. In the picture below, a hydrogen bomb explosion, the bomb having been placed in the lowest basement level and directed to the core, shows the resulting energy wave has reached the roof of the tower and the upper parts of the outer walls. On its way up, the waves of intense hydro-fire pressure partially penetrated about 100 floors of concrete and steel. Over ten million degrees of heat created by such a hydrogen bomb sublimated all water within the concrete in seconds. The water (or more specifically the Hydrogen content in the concrete) exploded extremely quickly into 24-fold volume which then totally pulverized the concrete and steel into a fine, white, and “hot” flour-like powder. All people, all office equipment and computers that were in the buildings immediately vaporized, turning instantly into heat and light. That is why almost no human remains of the nearly 3,000 victims and/or any recognizable office equipment residue was found in the ruins – yet thousands of offices were supposedly only “collapsed”from gravity. Where are the human remains of the victims??Also, thermonuclear radiation via hydrogen is absorbed in steel so quickly that steel heats up immediately well over its melting point 1585 °C (approx. 2890 °F) and also above its boiling point around 3000 C (approx. 5430 °F). In the pictures shown below, super hot groups of steel pillars and columns, torn from their walls by the nuclear pressure wave, are instantly sublimated. They immediately turn into a vaporized form, binding heat is then released as quickly as possible. Upwardly blooming blast clouds (a mini mushroom), are clearly visible in the picture below. Clearly, this can not be possible for a mere gravitational collapse or even for cutting charges which are used for energy release horizontally. Here you see the brown “energy cloud” of the explosion extending well over 63 meters in either direction of the 63 meter wide tower. This incredibly potent energy wave could not have been produced by a mere gravitational “collapse”. Steel pillars are turned into dust.Extremely hot, sublimating pieces are not created by too many demolition methods.For comparison, pictures of subterranean nuclear explosions where the explosion is blasting onto surface and into the air: WTC 2 Banberry 10 Kt undergroundRadioactivity released in the air creates shades of brown as the Electro-MagneticPulse knocks out all electrical devices within a specific, defined radius of theblast. (The subterranean nuke in the picture on the right is 10 times stronger than the small nuke on the left.) This is the primary reason why the FBI did not search the crime scene, and why the area was immediately cordoned off from the general public. Ground zeros of nuclear weapons are a public health risk and belong exclusively to the “experts” ofFEMA.Furthermore, normal fiery jet fuel conflagrations and planned demolitions do not remain extremely “hot” 5 to 10 days after the fires have been extinguished. However, hydrogen bomb sites remain thermally reactive and “hot” for days and even weeks. This is clearly demonstrated by the USGS calibrations of the WTC areas.Images of the World Trade Center Site Show Thermal Hot Spots on September 16 and 23, 2001. (Downloaded directly from the USGS Website –with their commentary and explanation.)Results of Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) remote sensing data and interpretations show the distribution and intensity of thermal hot spots in the area in and around the World Trade Center on September 16 and 23, 2001. Data collected on the 16th were processed, interpreted and released to emergency response teams on the 18th of September, 2001. The September 23 data were processed, interpreted and the results released on October 12, 2001. The images of the World Trade Center site show significant thermal hot spots on Sept. 16, 2001. By Sept.23, 2001, most of the hot spots had cooled or the fires had been put out. The AVIRIS instrument is a National Aeronautics and Space Administration (NASA) remote sensing instrument that measures upwelling spectral radiance in the visible through short-wavelength infrared. The instrument has 224 spectral channels (bands) with wavelengths from 0.37 to 2.5 microns (micrometers).In response to requests from the EPA through the USGS, NASA flewAVIRIS on a De Havilland Twin Otter over lower Manhattan at mid-day on September 16 and 23, 2001. For these deployments, the Twin Otter was flown at altitudes of 6,500 and 12,500 feet. The spectral data for the maps shown here were measured at 6,500 feet and have a spatial resolution (pixel spacing) of approximately 6 feet (2 meters).AVIRIS records the near-infrared signature of heat remotely. The accompanying maps are false color images that show the core affected area around the World Trade Center. Initial analysis of these data revealed a number of thermal hot spots on September 16 in the region where the buildings collapsed 5 days earlier. Analysis of the data indicates temperatures greater than 800oF. Over 3 dozen hot spots appear in the core zone. By September 23, only 4, or possibly 5, hot spots are apparent, with temperatures cooler than those on September 16 (Thermal Figure 1).The images (larger area shown below) also show vegetated areas as green. Water appears blue, and the smoke from the fires appears as a light blue haze. White and lighter blue areas are rooftops, roads, and concrete as well as dust and debris from the collapsed buildings. Dust, probably more than a millimeter thick, appears in shades of brown around the core WTC area on the 16th.On the September 16th, 2001 image (Thermal Figure 2), large areas around the World Trade Centers show brownish colors, indicating the debris. On September 20, 2001 there was a significant rain storm that washed away some of the dusty debris. Reduction of the distribution of dust/debris is apparent in the September 23 image (Thermal Figure 3), and can be attributed to the cleanup effort along with the rain.There are other red/orange spots that show in the images in the area south of the World Trade Center zone. These are hot spots from chimneys or heating exhaust vents and are normal and not other uncontrolled fires.The AVIRIS data were processed at the Jet Propulsion Laboratory (JPL) in Pasadena California where the data are calibrated to radiance and corrected for aircraft yaw, pitch, and roll. Acquisition and calibration ofAVIRIS data at JPL are under the direction of Robert O. Green. The data were then transmitted to the U.S. Geological Survey (USGS), Imaging Spectroscopy Group in Denver, Colorado, under the direction of Dr. Roger N. Clark. Atmospheric and ground calibrations were applied to derive apparent surface reflectance and maps were then made of surface materials. The USGS imaging spectroscopy group includes Dr. Gregg Swayze, Eric Livo, and Todd Hoefen. Thermal Figure 2. AVIRIS image from September 16, 2001. Hot spots show as orange and yellow areas. Yellow is hotter than red(because of color mixing in the way the 3-color image was produced). Thermal Figure 3. AVIRIS image from September 23, 2001. Only a couple of hot spots remain in view. Thermal Figure 4. Index for the locations of some of the hot spots observed on September 16, 2001.Temperature of the Hot SpotsRemote measurement of the temperature is difficult because the source of the thermal emission can be less than the field of view of the measuring instrument. In that case a thermal sensor has an ambiguous solution: a hotter temperature of a smaller area or lower temperature of a larger area can result in the same total received thermal radiation.A spectrometer, however, overcomes the ambiguity problem above, because the shape of the thermal spectrum can be used to derive a unique temperature, and the intensity gives the area of the emitting source. If a large enough spectral range is covered, a range of temperatures and the area of each can be derived. In the near infrared spectral range of AVIRIS, reflected solar radiation also contributes to the signal. The solution to the generalized problem involving all these effects is given in Clark (1979).We derived temperatures using two methods: calibrated radiance, and derived reflectance following Clark’s (1979) methods. In derived reflectance, thermal radiation is the Planck response divided by the solar spectrum. This has several effects: 1) the data are corrected for atmospheric absorption and scattering, 2) the reflected solar component can be readily assessed and compensated for, and 3) the ratio of the Black-Body response by the solar spectrum produces a very steep curve that is readily distinguishable from reflected sunlight and reflectance of surface materials.Simple temperature derivation from derived reflectance is illustrated in Thermal Figure 5a and b. Here the hot spot is assumed to fill the pixel. The thermal response of hot spot A (from Thermal Figure 4) shows the AVIRIS response higher than the 800 kelvin curve. The 800 Kelvin temperature is a lower limit to the temperature. While the upper limit might be the 900 Kelvin curve, we see the slopes do not match. As temperatures increase, the peak in Black Body emission moves to shorter wavelengths and the slope of the curve decreases at positions on the short wavelength side of the peak (the case here).Hot spot C (Thermal Figure 5b) shows similar effects. For hot spots covering the full area of the pixel, the temperature must be greater than 700 Kelvin. At about 1.3 microns, the model at 800 Kelvin matches the AVIRIS data, but the 800 Kelvin curve has a higher slope. This indicates the hot spot is smaller than the size of the pixel, but hotter than 800Kelvin.Solutions that include reflected solar radiation, hot spot temperature and hot spot area are shown in Thermal Figures 6a and b. Hot spot A, which from Thermal Figure 5 has a temperature greater than 800 Kelvin, is found to have a 1000 Kelvin temperature in a spot covering ~15% of a pixel, or 0.56 square meter. Similarly, hot spot C is found to have a 900 kelvin temperature over 20% of a pixel, or 0.8 square meter.The sensitivity of the solution of area and temperature is illustrated in Thermal Figure 7. An excellent fit is obtained for hot spot C with a 900 Kelvin spot filling 20% of the pixel. At 1000 Kelvin, only 8% is required but the fit is noticeably worse. For temperatures in the 800-1000 Kelvin range, temperature accuracy is estimated to be ± 30 Kelvin and the area ± 5%. For smaller spots, like spot G in Table 1, the temperature accuracy is similar, but the accuracy on such small areas is approximately +5%, 0.5%. For example, decreasing the temperature to 1000 Kelvin (from 1020 Kelvin) on spot G increases the fractional area to about 5%.Positions, temperatures and equivalent areas for hot spots A-H are given in Table 1 and the geometrically rectified location map is shown in Thermal Figure 8.Thermal Figure 5a. Thermal Figure 7. Table 1 Thermal Hot Spot Data Location Temperature AreaHot Spot N Latitude W Longitude (Kelvin) % FOV sq meterA 40o 42′ 47.18″ 74o 00′ 41.43″ 1000 15 0.56B 40o 42′ 47.14″ 74o 00′ 43.53″ 830 2 0.08 C 40o 42′ 42.89″ 74o 00′ 48.88″ 900 20 0.8 D 40o 42′ 41.99″ 74o 00′ 46.94″ 790 20 0.8E 40o 42′ 40.58″ 74o 00′ 50.15″ 710 10 0.4 F 40o 42′ 38.74″ 74o 00′ 46.70″ 700 10 0.4G 40o 42′ 39.94″ 74o 00′ 45.37″ 1020 1 0.04H 40o 42′ 38.60″ 74o 00′ 43.51″ 820 2 0.08Positions are in degrees-minutes-decimal seconds, datum WGS84.Position accuracy is estimated to be approximately +/- 6 meters (18feet).Thermal Figure 8. Geometrically rectified image of the WTC core region showing hot spot locations.
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