Pack ice 1,217 Paleobotany 1,105 Paleoclimatology 14,661 Paleoecology 3,152 Paleoenvironment 4,131 Paleogene 920 Paleogeography 1,582 Paleohydrology 543 Paleomagnetism 1,276 Paleontology 1,914 Paleo-oceanography 2,280 Paleotemperature 1,845 Paleozoic 1,247 Palynology 526 Palynomorphs 1,801 Particles 695 Particle size distribution 777 Patterned ground 866 Pavements 1,275 Peat 2,335 Pedology 554 Performance 709 Periglacial environment 568 Periglacial features 1,689 Periglacial processes 1,982 Periodic variations 1,100 Permafrost 11,522 Permafrost beneath structures 2,699 Permafrost depth 621 Permafrost distribution 2,610 Permafrost hydrology 2,885 Permafrost physics 802 Permafrost preservation 694 Permafrost structure 1,380 Permafrost thermal properties 1,569 Permafrost thickness 977 Permeability 867 Petroleum 1,672 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 2,163 Physiology 1,271 Physiology--Human 588 Phytoplankton 1,289 Pigments 918 Piles 660 Pipelines 1,790 Pisces 1,187 Pisces--Morphology 525 Pisces--Physiology 847 Planar bedding structures 578 Planets 1,316 Plankton 3,667 Plankton--Phytoplankton 1,047 Planning 611 Plantae 4,355 Plant ecology 4,338 Plant physiology 1,590 Plants (botany) 844 Plant tissues 527 Plate tectonics 1,033 Pleistocene 9,752 Pliocene 698 Plutonic rocks 596 Podsol 540 Polar atmospheres 3,355 Polar regions 1,652 Polar stratospheric clouds 666 Pollen 1,491 Pollutants 1,873 Pollution 3,841 Polymers 721 Polynyas 1,074 Porosity 1,127 Porous materials 599 Power line icing 868 Precambrian 1,130 Precipitation 553 Precipitation (meteorology) 9,008 Prediction 2,527 Prefabrication 560 Pressure 1,147 Pressure ridges 836 Preventive measures 581 Primary productivity 1,380 Processes 563 Productivity 1,848 Profiles 1,911 Programs 1,431 Protection 1,399 Proterozoic 830 Protista 1,770 Provenance 700