Pack ice 1,217 Paleobotany 1,105 Paleoclimatology 14,657 Paleoecology 3,152 Paleoenvironment 4,128 Paleogene 920 Paleogeography 1,582 Paleohydrology 542 Paleomagnetism 1,276 Paleontology 1,914 Paleo-oceanography 2,280 Paleotemperature 1,843 Paleozoic 1,247 Palynology 526 Palynomorphs 1,799 Particles 695 Particle size distribution 777 Patterned ground 864 Pavements 1,275 Peat 2,332 Pedology 554 Performance 709 Periglacial environment 565 Periglacial features 1,679 Periglacial processes 1,981 Periodic variations 1,100 Permafrost 11,442 Permafrost beneath structures 2,699 Permafrost depth 621 Permafrost distribution 2,607 Permafrost hydrology 2,879 Permafrost physics 802 Permafrost preservation 694 Permafrost structure 1,380 Permafrost thermal properties 1,563 Permafrost thickness 971 Permeability 864 Petroleum 1,669 Petroleum exploration 822 Petroleum industry 944 Petrology 3,870 PH 663 Phase transformations 2,217 Photochemistry 737 Photography 539 Photointerpretation 779 Photosynthesis 1,437 Physical properties 2,160 Physiology 1,271 Physiology--Human 588 Phytoplankton 1,289 Pigments 918 Piles 660 Pipelines 1,784 Pisces 1,187 Pisces--Morphology 525 Pisces--Physiology 847 Planar bedding structures 578 Planets 1,316 Plankton 3,667 Plankton--Phytoplankton 1,047 Planning 610 Plantae 4,350 Plant ecology 4,337 Plant physiology 1,590 Plants (botany) 844 Plant tissues 527 Plate tectonics 1,033 Pleistocene 9,746 Pliocene 698 Plutonic rocks 596 Podsol 540 Polar atmospheres 3,355 Polar regions 1,652 Polar stratospheric clouds 666 Pollen 1,489 Pollutants 1,871 Pollution 3,838 Polymers 721 Polynyas 1,074 Porosity 1,123 Porous materials 598 Power line icing 868 Precambrian 1,130 Precipitation 553 Precipitation (meteorology) 9,005 Prediction 2,523 Prefabrication 560 Pressure 1,146 Pressure ridges 836 Preventive measures 580 Primary productivity 1,380 Processes 559 Productivity 1,847 Profiles 1,910 Programs 1,431 Protection 1,399 Proterozoic 830 Protista 1,770 Provenance 699