Design of Miniature Temperature Recorder Based on PIC24F

The designing scheme for PIC24F-based miniature temperature recorder was summarized and MCU was introduced. The scheme included sensitive compo-nents, MCU （PIC24FJ128GA106）, as wel as the PC terminal for settings, col ec-tions and temperature read as wel as data processing. And the principle of design was introduced, including measurement module introduction, real-time clock and de-vice calibration section. This paper provided a theoretical basis for the application of PIC24F-based miniature temperature recorder.

Predictions of El Nino,La Nina and Record Low Chicago Temperature by Sunspot Number

The El Nino Index, defined as 4 intensities (very strong, strong, moderate, weak) in Oceanic Niño Index (ONI), was positively correlated with the average sunspot number at each intensity. The La Niña Index, defined as 3 intensities (strong, moderate, weak) in ONI, was negatively correlated with the average sunspot number from 1954 to 2017. It appears that very strong El Niño events occur frequently during the maximal sunspot number while strong La Niña events more often occur during the minimal sunspot number. Since greenhouse-gas is continuously increased, it is therefore proposed that the maximal sunspot number is a major parameter for prediction of El Niño while the minimal sunspot number applies in the same way for La Niña. El Nino/La Nina events can be classified as four typical cases depending upon the submarine volcanic activities at seamounts in Antarctica and South America. The Sea Surface Temperature (SST) of the South and Central Americas are warmer than SST of East Australian Current (EAC), due to the strong volcanic eruptions in the Seamounts and the Ridges in South and Central Americas. This results in the Central Pacific Current (CPC) flowing from east to west due to the second law of thermodynamics for thermal flow from hot source to cold sink. In contrast the opposite direction is made if SST in EAC is warmer than SST in the Central/South American Seamounts and Ridges, due to the strong volcanic eruptions in the Antarctic Seamounts and Ridges. Chicago was selected as a case study for the relationship between extreme cold weather conditions and minimal sunspot number. Previous attempts at predicting weather patterns in Chicago have largely failed. The years of the record low temperatures in Chicago were significantly correlated with the years of the minimal sunspot number from 1873 to 2019. It is forecast that there may occur a weak La Niña in 2019 and another record low temperature in Chicago in January of 2020 due to the phase of the minimal sunspot number in 2019. It may be possible to predict very strong El Nino events with the year of maximal sunspot number as El Niño Index (R2 = 0.7363) and the years of strong volcanic eruption in the Galapagos Hot Spot (GHS) (R2 = 0.9939), respectively. An El Niño event is thus expected during the year of strong volcanic eruption in the GHS. Strong La Niña events can be expected during the year of minimal sunspot number with La Niña Index (R2 = 0.9922). Record low temperatures in Chicago can be also predicted (R2 = 0.9995) during the year of the minimal sunspot number, as was recently the case in January, 2019.

Near-surface Geothermal Gradient Observation and Geothermal Analyses in the Xianshuihe Fault Zone,Eastern Tibetan Plateau

The Xianshuihe fault（XSHF） zone, characterized by intense tectonic activity, is located at the southwest boundary of the Bayan Har block, where several major earthquakes have occurred, including the 2008 Wenchuan and the 2013 Lushan earthquakes. This study analysed underground temperature sequence data for four years at seven measuring points at different depths（maximum depth： 18.9 m） in the southeastern section of the XSHF zone. High-frequency atmospheric noise was removed from the temperature sequences to obtain relatively stable temperature fields and heat fluxes near the measurement points. Our measurements show that the surrounding bedrock at（the seven stations distributed in the fault zone） had heat flux values range from-41.0 to 206 m W/m^2, with a median value of 54.3 m W/m^2. The results indicate a low heat flux in the northern section of DaofuKangting and a relatively high heat flux in the southern section of Kangting, which is consistent with the temperature distributions of the hot springs near the fault. Furthermore, our results suggest that the heat transfer in this field results primarily from stable underground heat conduction. In addition, the underground hydrothermal activity is also an obvious factor controlling the geothermal gradient.

Determination of seepage velocity in streambed using temperature record of Russian River, USA

The vertical seepage velocity is an important parameter in the groundwater-surface water （GW-SW） exchange process. It is reported that the periodical fluctuated temperature record of the streambed can be used to determine the seepage velocity. Based on a 1-D flow and heat transport model with a sinusoidal temperature oscillation at the upstream boundary, a new analytical model is built. This analytical model can be used to determine the seepage velocity from the amplitude ratio of the deep and shallow test points. The process of calculation is discussed. The field data are superimposed by multi-periods, so the spectrum analysis and the data filtering are desirable. For the typical seepage medium, the analytical model is effective to compute the seepage velocity between -2 m/d and 6 m/d by using the record of the daily period fluctuation. The temperature time-series analytical model is used to determine the upwards seepage under the condition that the spacing of test points is small （less than 0.2 m）. Lastly, a case study for the Russian River shows that this model is very convenient to determine the temporal changes of the GW-SW exchange.

Researcher Creates First Temperature Record For The Great Plains

越来越多的学者关注世界各地的温度变化,不光是近年的气温,若干年前甚至史前的温度变化对研究也很重要。美国北部大平原地区一直没有气温记录,但是现在研究人员运用新方法测出了这一地区自12,000年前以来的温度变化。他们是怎么做的呢?