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Dust storms are an important component of the global climate system. At the same time, they also bear a risk for human health by causing pulmonary diseases. Today, East Asian dust storms account for as much as half of the global dust emissions and temporarily affect highly populated areas. Therefore, understanding their mechanisms and predicting their evolution under warmer near-future climate conditions is of major interest. The mid-Pliocene Warm Period (mPWP; 3.264–3.025 Ma) is considered one of the best analogues from the past for anthropogenic climate change. Consequently, understanding the climate dynamics and associated environmental change during the mPWP can help with predicting the environmental effects of warmer-than-present climates. In order to reconstruct Asian dust storm evolution during the mPWP we have analyzed a sediment core from the northern South China Sea (SCS) for its elemental composition, grain-size variations and radiogenic isotope signature for the interval spanning from 3.69 to 2.96 Ma. We show that shortly after the first strong northern hemisphere glaciation (Marine Isotope Stage [MIS] M2; 3.25 Ma) atmospherically transported dust appeared in the northern SCS and this dust deposition prevailed throughout the mPWP. Atmospheric dust input further intensified with the onset of the MIS KM2 glaciation at 3.15 Ma, with distinct and strong dust storms occurring periodically from that time onwards. The increase in atmospherically transported dust can be attributed to the cooling and drying of interior Asia over the course of the mPWP along with an intensification of the East Asian Winter Monsoon and a potential southward shift of the westerlies.

Paleo-typhoon activity and its correlation with El Nino Southern Oscillation (ENSO) during the late Holocene has been reported by numerous studies, but our understanding of the impacts of typhoons as natural disturbance events on subtropical forest ecosystems remains unclear. In this study, we used a multi-proxy method, including pollen, grain size, and the ratios of Sr/Ti and Rb/Ti from XRF-scanning measurements, on a sediment core from Tunlumei Pond (TLM) to reconstruct vegetation dynamics and the records of natural disturbances, such as heavy rainfalls, earthquakes, or typhoons, in central alpine Taiwan during the past 2400 calibrated years before the present (cal yr BP, where “present” refers to 1950 AD). The trend in variation between the percentages of upper montane forests and PC1 value indicates that the cold/dry climate changed to a warm/humid climate from 1800 cal yr BP upward, corresponding to the Roman Warm Period. This local change might be corresponded to regional trend and relative to the East Asian summer monsoon fluctuation. Coarse grain particles associated with the transition of the pollen zone indicate frequent and/or strong natural disturbances at 1510 cal yr BP and the impacts of the early Little Ice Age (LIA) during 530–480 cal yr BP. The palaeoecological record of TLM provides very useful information for both decision making and policy planning in present and future subtropical forest management, as well as restoration after a catastrophic event.

Influenced by rapid tectonic activities and frequent typhoons, Taiwan is unique in having extremely high rates of uplift, precipitation, denudation, and sedimentation. These dynamic surface processes not only influence landscape evolution and river behavior, but severely affect human societies both at present and in the past. Particularly, mass-movement and flooding events caused by earthquakes and/or typhoons may introduce a huge amount of sediments into river systems, and result in natural hazards due to consequent river-aggradation. The Iron Age Kiwulan Site is a recently discovered archaeological site situated on the margin of the Lanyang Plain in northeastern Taiwan. In its deposits, a cultural hiatus centered on 1150–1350 CE was recognized suggesting that the settlement was abandoned for two hundred years before being recolonized. To find the cause of this cultural break, the river-aggradation history since 800 CE has been reconstructed by a source-to-sink approach using multiple lines of evidence from the Lanyang Source-to-Sink System, northeastern Taiwan. Two particular river-aggradation events that occurred during 875–925 CE and 1400–1500 CE were traced from their source (upland river terrace), through floodplain lakes to their ultimate sink (the Okinawa Trough and Hoping Basin of the Pacific Ocean). However, as these extreme river-aggradation events occurred either significantly earlier or later than the cultural hiatus, dramatic climate and earthquake events are not likely to be the direct causes for the cultural hiatus. Instead, river migration might have been the reason for the abandonment and return of the Kiwulan settlements.

A key aspect of East Asian climate is its summer monsoonal system which influences nearly one-third of the world's population. Recent results indicate that the primary response of the East Asian summer monsoon (EASM) to anthropogenic forced climate warming may be a shift in geographical range instead of an intensity change, which would lead to spatial coexistence of floods and droughts over southeastern Asia. The predicted EASM variability in the future has made it paramount to study its past changes and the associated tempo-spatial pattern of aridity and humidity in its purview. In order to decipher past changes in EASM, we applied a multi-proxy geochemical approach to the sediment core ORI-891-16-P1 located in the northern South China Sea. The position of this sediment core on top of a seamount makes it uniquely sensitive to changes in the terrigenous input into northern South China Sea unbiased by sea level-induced downslope transport processes. Utilizing the ln(Ti/Ca) ratio throughout the sediment sequence we trace terrigenous influx changes reflecting EASM prevalence during the last ~40 kyrs. Based on the comparison of our results to previous studies we infer that the Last Glacial Maximum (LGM; ~ 20 ka BP) was characterized by a steep N-S humidity gradient. This spatial pattern was in line with a southward shift or contraction of the summer monsoonal trough of 10–15° from its current position toward the centre of the South China Sea. Superimposed on orbital time scale fluctuations we also find strong indication of millennial-scale variability related to Heinrich Stadials. The impact of Heinrich Stadials on the EASM seems amplified during insolation minima, while high summer insolation seems to buffer the monsoonal system to such perturbations. We infer that (i) the humidity-aridity distribution during the LGM mimics predictions of the proposed future EASM configuration, and (ii) that the sensitivity of the EASM to weakening in the Atlantic Meridional Overturning Circulation is the strongest since the last glacial.

Five sediment cores from the Lomonosov Ridge and the Morris Jesup Rise north of Greenland show the history of sea-ice coverage and primary productivity over the last two glacial cycles. Variations in Manganese content, benthic and planktonic foraminifera, bioturbation, and trace fossil diversity are interpreted to reflect differences in sea-ice cover and sediment depositional conditions between the identified interglacials. Marine Isotope Stage (MIS) 1 and MIS 2 are represented by thin (

We provide an integrated stratigraphy for the southern margin of the Indo-Pacific Warm Pool back to 3.2 million years ago (Ma) from ODP Site 1115, Hole B (9o11'S, 151o34'E, water depth 1149 m, 0–217 m below sea floor), the only hole with core recovery beyond 4.4 m. An initial age model based on 14 calcareous nannofossil datums, 5 planktonic foraminiferal biostratigraphic events and 12 magnetic polarity reversals is refined by planktonic foraminiferal Globigerinoides sacculifer (300–355 μm) δ18O stratigraphy. The planktonic δ18O record with an average 3–4 kyr resolution matches the global stack LR04 (Lisiecki and Raymo, 2005). The 41-kyr obliquity and 100-kyr eccentricity patterns show good correlation between the LR04 and the dataset presented herein. The precession amplitude matches eccentricity, supporting the established stratigraphy. Sedimentation rates at Hole 1115B have decreased from 9.3 to 4.5 cm/kyr during the past 3.2 Ma toward present, mainly due to the gradual deepening of the Woodlark Basin. The planktonic δ18O record from Site 1115 matches the global climate evolution well.

The paleoclimatic sensitivity to atmospheric greenhouse gases (GHGs) has recently been suggested to be nonlinear, however a GHG threshold value associated with deglaciation remains uncertain. Here, we combine a new sea surface temperature record spanning the last 360,000 years from the southern Western Pacific Warm Pool with records from five previous studies in the equatorial Pacific to document the nonlinear relationship between climatic sensitivity and GHG levels over the past four glacial/interglacial cycles. The sensitivity of the responses to GHG concentrations rises dramatically by a factor of 2–4 at atmospheric CO2 levels of >220 ppm. Our results suggest that the equatorial Pacific acts as a nonlinear amplifier that allows global climate to transition from deglacial to full interglacial conditions once atmospheric CO2 levels reach threshold levels.

The Intertropical Convergence Zone (ITCZ) encompasses the heaviest rain belt on the Earth. Few direct long-term records, especially in the Pacific, limit our understanding of long-term natural variability for predicting future ITCZ migration. Here we present a tropical precipitation record from the Southern Hemisphere covering the past 282,000 years, inferred from a marine sedimentary sequence collected off the eastern coast of Papua New Guinea. Unlike the precession paradigm expressed in its East Asian counterpart, our record shows that the western Pacific ITCZ migration was influenced by combined precession and obliquity changes. The obliquity forcing could be primarily delivered by a cross-hemispherical thermal/pressure contrast, resulting from the asymmetric continental configuration between Asia and Australia in a coupled East Asian–Australian circulation system. Our finding suggests that the obliquity forcing may play a more important role in global hydroclimate cycles than previously thought., Predicting future migrations in the Intertropical Convergence Zone—Earth's heaviest rain belt—is limited by a lack of long-term records. Here, the authors present a 282 kyr precipitation record from the Papua New Guinea coast and show that obliquity forcing plays a more important role than previously recognized.

Packet losses and errors are common through current wireless transmission due to signal decay, barriers in-between and other environmental related reasons. Although there are many ways to correct these errors, there is no one can deal with them immediately. For the efficient use of energy to achieve the purpose of energy conservation, and use the smallest energy to implement monitoring more, rapid implementation of parallel processing, a division of cooperation can be real-time monitoring without individual inquiries. If data are sent in hardware method, safer transmission can be reached by simply modify the hardware. Adopted the principle of variable packet, each single-chip can act as transceiver at any time, automatically send or emergency call by turns. The use of searching the initial symbols and the suspension symbols of the interpretation of the way to transmit the information and the related content. Signals can be sent to the extensions by monitoring and management of the host, also can be transferred to another host through cross-regional, as well as the transmitting DATA can be mounted other messages without wasting time. By checking the connection between any two adjacent bytes, problems like signal decay can be solved. At the meantime, it can correct errors automatically, to prevent interferences, and fortify the safety and encryption of wireless transmission.

With the penetration of the Internet and the rapid development of information technology, the secure transmission of the text and image herewith gets a great deal of attention. The traditional methods of encryption can only maintain the information security. However, the information could be cracked and to proceed criminal acts by the illegal use of the relevant information. Therefore, it is necessary to apply both time-varying and information-varying of encryption/decryption methods to enhance information security.

In this study, we present a method to observe the location and the length of carbon nanotubes under an optical system instead of SEM. Firstly, the carbon nanotubes were synthesized by using mixed methane and ethylene carbon source in the chemical vapor deposition (CVD) as reported in W. Kim et al. (2002). Then, the carbon nanotubes were coated with amorphous carbon by blowing ethanol vapor into the furnace at 900 /spl deg/C. The observations of SEM and TEM show that each carbon fiber consists of one carbon nanotube and a great deal of amorphous carbon. The diameters of the carbon fibers, around 500 nm, are so large that they can be easily observed and estimated from the optical images. For example, the longest length of carbon fiber observed in this experiment can exceed 2 cm. In addition, the most of the carbon fibers are well-aligned due to floating catalyst as presented in S. Huang et al. (2003). This method is useful as locating of suspended carbon nanotubes or manipulating nanotubes under the optical system.