Pack ice 1,217 Paleobotany 1,105 Paleoclimatology 14,659 Paleoecology 3,152 Paleoenvironment 4,130 Paleogene 920 Paleogeography 1,582 Paleohydrology 542 Paleomagnetism 1,276 Paleontology 1,914 Paleo-oceanography 2,280 Paleotemperature 1,844 Paleozoic 1,247 Palynology 526 Palynomorphs 1,800 Particles 695 Particle size distribution 777 Patterned ground 865 Pavements 1,275 Peat 2,333 Pedology 554 Performance 709 Periglacial environment 567 Periglacial features 1,685 Periglacial processes 1,982 Periodic variations 1,100 Permafrost 11,469 Permafrost beneath structures 2,699 Permafrost depth 621 Permafrost distribution 2,608 Permafrost hydrology 2,881 Permafrost physics 802 Permafrost preservation 694 Permafrost structure 1,380 Permafrost thermal properties 1,565 Permafrost thickness 975 Permeability 865 Petroleum 1,671 Petroleum exploration 823 Petroleum industry 944 Petrology 3,870 PH 663 Phase transformations 2,217 Photochemistry 737 Photography 539 Photointerpretation 779 Photosynthesis 1,437 Physical properties 2,162 Physiology 1,271 Physiology--Human 588 Phytoplankton 1,289 Pigments 918 Piles 660 Pipelines 1,788 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 4,353 Plant ecology 4,338 Plant physiology 1,590 Plants (botany) 844 Plant tissues 527 Plate tectonics 1,033 Pleistocene 9,749 Pliocene 698 Plutonic rocks 596 Podsol 540 Polar atmospheres 3,355 Polar regions 1,652 Polar stratospheric clouds 666 Pollen 1,490 Pollutants 1,871 Pollution 3,838 Polymers 721 Polynyas 1,074 Porosity 1,125 Porous materials 598 Power line icing 868 Precambrian 1,130 Precipitation 553 Precipitation (meteorology) 9,007 Prediction 2,525 Prefabrication 560 Pressure 1,146 Pressure ridges 836 Preventive measures 581 Primary productivity 1,380 Processes 561 Productivity 1,848 Profiles 1,910 Programs 1,431 Protection 1,399 Proterozoic 830 Protista 1,770 Provenance 699