Archive for September, 2013
Tuesday, September 24th, 2013
I just traveled quite a distance to come to the Asian Geospatial Forum Conference in Malaysia on the new Dreamliner – 787. Six hours into the flight we had to back track to Anchorage to avoid an emergency landing in Russia, all because our flaps were not working. To accomplish a flapless landing the pilots had to speed up and drop down fast. In three or four minutes we descended about 5000 feet! They warned us, and I quote, “this is a serious but doable approach, remain calm and review the safety brochure.” The ability of the pilots to control or stabilize the aircraft to achieve a safe, albeit rough landing, got me thinking about our Lear jets used to collect interferometric synthetic aperture radar (IFSAR or InSAR) data. Ok, maybe I am a radar geek if that is what I am thinking about in an emergency landing?
In many cases, we fly in remote areas where there is little opportunity for us to deploy ground control, but still need to acquire high resolution data. How is it possible to achieve high resolution data collections without the deployment of in-scene ground control? The answer lies in the stability of our aircraft and our ability to precisely know where our two radar antennae are with respect to the ground we are mapping and our nominal flight trajectory (planned flight path).
Tuesday, September 17th, 2013
Colorado is a semi-arid state, which typically indicates a climatic region that receives precipitation below potential evapo-transpiration, but not extremely. The climate is typically associated with dry winters, wetter springs and summer, highly changeable weather, frequent wind, and the occasional monstrous thunderstorms with damaging hail. Yet, we Coloradans are experiencing catastrophic flood events where, folks on ridges are not free from the reaches of water flowing downhill, from the sky, or from the saturated water table from below. Where has sunny Colorado gone this past week?
Friday, September 13th, 2013
Successful mining exploration relies heavily on the accuracy of the geology map layer that depicts the spatial distribution of geologic units and structure. Often times, however, existing geologic maps vary in quality and accuracy due to differences in purpose of mapping, scale or level of details, inconsistency in nomenclatures, and types of map projection/registration. Conventional mapping methods of bringing existing geologic maps to the desired quality level or standard will entail a large amount of time and effort, and consequently will also drastically slow down mineral exploration. The creation of digital geology maps (map components: topography, structure, and lithology) from the desktop using interferometric syntehtic aperture radar (IFSAR or InSAR) provides a cost effective method, espeically in remote dense vegetated areas.
Tuesday, September 10th, 2013
Oil Palm plantations cover more than 700,000 hectares in East Sabah, Malaysia. Sabah also has the highest yield of oil palm fresh fruit bunch per hectare, in Asia. Moreover, oil palm crops are an important agriculture sector for the Malaysian economy in terms of export earnings, since it contributes to >30% of the total income from exports. Accurate and reliable three dimensional and near-real time geospatial information is needed for sustainable oil palm plantation management, especially on plant quality, health, and crop yield calculations.
Tuesday, September 3rd, 2013
Synthetic aperture radar (SAR) sensors “see” the ground in a different way from optical sensors such as SPOT, aerial cameras, or the human eye; therefore, radar images have certain characteristics that are fundamentally different from those in images collected by optical sensors. The key then to understanding and interpreting radar images lies in the answer to this question: What happens to the electromagnetic energy in a radar pulse as it meets the terrain being imaged, interacts with the terrain, is recorded by the radar sensor, and subsequently is processed to generate a radar image? Answering this question is not easy. However, with the resolution of SAR sensors are getting better and better, details provided in, for example a 50 cm pixel, help our eyes to discern topographic features more readily than ever before.