Byw mewn cylchfa weithredol The Physical World Y Byd Ffisegol 3 Living in an Active Zone Byw mewn cylchfa weithredol How can the risks associated with volcanic and earthquake zones be reduced? Sut gellir lleihau ar yr peryglon sy’n gysylltiedig â chylchfaoedd folcanig a daeargryn? 2.1 How are volcanoes monitored and what does this tell us about their state? 2.1 Sut mae llosgfynyddoedd yn cael eu monitro a beth mae hyn yn dweud wrthym am eu cyflwr?

Synhwyro o bell hydroleg nwy seismigedd Dadffurfiant tir Mesuriadau geoffisegol

Seismigedd Seismicity Defnyddio rhwydwaith o seismomedrau i fesur cynnydd mewn daeargrynfeydd Using a network of seismometers to measure the increase in earthquakes Hydroleg Hydrology The pattern of valleys can influence where lahars go. Automatic sensors can detect the passage of a lahar. Mae’r patrwm o ddyffrynoedd yn gallu dylanwadu ble mae lahar yn mynd. Defnyddir offer awtomatig.

Monitoring ground deformation Monitro dadffurfiant tir Changes at the surface tell us about the sub-surface Mae newidiadau ar y wyneb yn helpu i ni ddeall o dan y wyneb Mesur pellteroedd gyda meidrydd pellter electronig Measuring distances using an electronic distance meter Defnyddio GPS i fesur uchder tir a lleoliadau o gwmpas llosgfynydd Using a GPS to measure land height and locations around a volcano Interferometric Synthetic Aperture Radar Defnyddio radar i ddangos sut mae’r tir wedi symud Using radar to show earth deformation Defnyddio gwyromedr i fesur ongl llethrau Using a tiltmeter to measure slope angles around a volcano Mesur nwyon i weld os oes newidiadau Measuring the content of volcanic gases to see if there are changes

Science is getting better Mae gwyddoniaeth yn gwella People feel safer with technological advances Monitoring equipment that can foretell volcanic activity They can measure the escape of gas (sulphur dioxide – bad egg smell) Small earthquakes which act as a warning Swelling of the sides of the volcano also warns of things to come Quakeproof construction techniques are becoming more advanced. But so far we are no closer to being to time earthquakes accurately Mae pobl yn teimlo’n saffach gyda gwelliannau technolegol Mae offer monitro yn gallu rhagweld gweithgaredd folcanig. Maent yn gallu mesur - nwy yn gollwng (swlffwr deiocsid – oglau o wyau drwg!!) - daeargrynfeydd bach sydd fel rhybudd - ochrau’r llosgfynydd yn chwyddo Mae dulliau adeiladu a gwrthsefyll daeargryn yn gwella Ond nid ydym yn gallu rhagweld pryd fydd daeargryn yn digwydd

What To Do If a Volcano Erupts BEFORE: Learn about your community warning systems and emergency plans. Be prepared for the hazards that can accompany volcanoes: Make evacuation plans. If you live in a known volcanic hazard area, plan a route out and have a backup route in mind. Develop an emergency communication plan. In case family members are separated from one another during a volcanic eruption (a real possibility during the day when adults are at work and children are at school), have a plan for getting back together. Ask an out-of-state relative or friend to serve as the "family contact," because after a disaster, it's often easier to call long distance. Make sure everyone knows the name, address, and phone number of the contact person. Have disaster supplies on hand: * Flashlight and extra batteries * First aid kit and manual * Emergency food and water * Non-electric can opener * Essential medicines * Dust mask * Sturdy shoes * Get a pair of goggles and a throw-away breathing mask for each member of the household in case of ashfall.

PREDICTION & PREPARATION RHAGWELD A DARPARU PREDICTION RHAGWELD Earthquakes are very hard to predict * Mae’n anodd rhagweld daeargrynfeydd Scientists can search for clues: * Gall gwyddonwyr chwilio am gliwiau changes in well water levels - newidiadau yn lefel dŵr daear gas emissions - allyriadau nwyon cracks appearing in rocks - craciau’n ymddangos mewn creigiau even strange animal behaviour!! - ymddygiad od gan anifeiliaid Computers can analyse data to forecast future earthquakes BUT they can’t be predicted accurately as they occur unexpectedly. Gall cyfrifiaduron ddadansoddi dat er mwyn rhagweld daeargrynfeydd yn y dyfodol OND nid ydynt yn gallu fod yn fanwl achos eu bod yn digwydd heb rybudd

Viewing platform Laser reflector Levelling surveys Tiltmeter and gravitometer Animal behaviour Existing fault line Water level in wells Radon gas counter Magnetometer and resistometer Creep meter and gravitometer Strainmeter Seismograph Water table Ways of monitoring which can help predict earthquakes Dulliau monitro all fod o gymorth i ragweld daeargryn

PREPARATION DARPARU Good planning and preparation can reduce the effects of tectonic hazards EMERGENCY DRILLS are held to practise what to do in the event of an earthquake INFORMATION on emergency procedures can be made available to the public (e.g. in school classes, pamphlets, newspapers), sheltering under a table or avoiding standing next to walls can save your life! EMERGENCY PLANS can be drawn up by the local authorities and government and practised in order to reduce damage, death and injury MONITORING helps predict when hazards are coming so people can be warned Gall cynllunio a darparu leihau’r effeithiau o bryglon tectoneg Cynhelir DRILIAU ARGYFWNG er mwyn ymarfer bethi’w wneud os ddigwydd daeargryn. Gellir cyhoeddi GWYBODAETH ar beth i’w wneud (e.e. mewn ysgolion, pamffledi, papurau newydd), gallai cysgodi o dan bwrdd neu osgoi sefyll nesaf i wal achub eich bywyd! Gall awdurdodau lleol a chenedlaethol greu CYNLLUNIAU ARGYFWNG er mwyn lleihau difrod, marwolaeth ac anafiadau. Mae MONITRO yn helpu rhagweld pryd mae peryglon yn dod fel gellir rhybuddio pobl.

PREPARATION DARPARU FAMILIES can organise supplies of food and water, dust masks, spare clothes, basic medical supplies, shelters, torches, batteries, mobile phones and other useful stuff EMERGENCY SERVICES such as the Police, Fire Brigade and Ambulance service can be well prepared to deal with any hazard EMERGENCY SUPPLIES of water and power can be organised in advance BUILDING & ROAD DESIGNS can be planned for earth movements so they don’t collapse under the strain e.g. New skyscrapers in earthquake zones can be built with a computer controlled counterweight, cross bracings and special foundations to reduce the impact of an earthquake Gall TEULUOEDD drefnu cyflenwad o fwyd a dŵr, mygydau llwch, dillad sbar, cyflenwadau meddygol, cysgodfeydd, tortsys, bateris, ffonau symudol ac ati Gallai GWASANAETHAU ARGYFWNG fel heddlu, brigad dân ac ambiwlans fod wedi paratoi yn dda er mwynd elio ag unrhyw berygl Gellir CYNLLUNIO ADEILADAU A FFYRDD i wrthsefyll symudiadau daear fel nad ydynt yn dymchwel e.e. mae adeiladau uchel gyda technegau arbennig.