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Considering pollinators' ecosystem services in the remediation and restoration of contaminated lands: Overview of research and its gaps

The concept of ecosystem services provides a useful framework for understanding how people are affected by changes to the natural environment, such as when a contaminant is introduced (e.g., oil spills, hazardous substance releases) or, conversely, when contaminated lands are remediated and restored. Pollination is one example of an important ecosystem service; pollinators play a critical role in any functioning terrestrial ecosystem. Other studies have suggested that consideration of pollinators' ecosystem services could lead to better remediation and restoration outcomes. However, the associated relationships can be complex, and evaluation requires synthesis from numerous disciplines. In this article, we discuss the possibilities for considering pollinators and their ecosystem services when planning remediation and restoration of contaminated lands. To inform the discussion, we introduce a general conceptual model of how pollinators and the ecosystem services associated with them could be affected by contamination in the environment. We review the literature on the conceptual model components, including contaminant effects on pollinators and the direct and indirect ecosystem services provided by pollinators, and identify information gaps. Though increased public interest in pollinators likely reflects increasing recognition of their role in providing many important ecosystem services, our review indicates that many gaps in understanding—about relevant natural and social systems—currently impede the rigorous quantification and evaluation of pollinators' ecosystem services required for many applications, such as in the context of natural resource damage assessment. Notable gaps include information on non-honeybee pollinators and on ecosystem services beyond those benefitting the agricultural sector. We then discuss potential research priorities and implications for practitioners. Focused research attention on the areas highlighted in this review holds promise for increasing the possibilities for considering pollinators' ecosystem services in the remediation and restoration of contaminated lands.

Integrated Environmental Assessment and Management

Lahars: Origins, behavior and hazards

Volcanic debris flows that originate at potentially active volcanoes are called lahars. Lahars are like debris flows in non-volcanic terrain but can most notably differ in origin and size. Primary lahars occur during eruptions and may have novel origins such as turbulent mixing of hot rock moving across ice- and snow-clad volcanoes and eruptions through crater lakes. Lahars range in volume to more than a cubic kilometer (10 9 m 3 ), with the biggest ones caused by huge deep-seated flank collapses of water-saturated edifice rock. Because they can be so voluminous, can have high water contents, and commonly can be clay rich, these lahars can travel tens to even hundreds of kilometers. Long transport causes evolution of flow types from flood flow to hyperconcentrated flow to debris flow. Lahars capable of traveling far downstream are commonly sufficiently liquefied that they drape valley slopes and leave behind thin deposits as they pass downstream. Only in valley bottoms are lahars likely to emplace thick deposits, and even there the deposits are apt to be much thinner than peak flow depths. Flows with long transport change character with time and distance downstream. Deposits, especially those in valley bottoms, can accrete during intervals that represent a significant proportion of the time it takes the flow to pass (typically minutes). The combination of flows changing character and their progressive accretion imposes distinctive characteristics on their deposits such as normal and inverse grading. Historically, lahars have caused thousands of fatalities and destroyed entire towns. Perhaps the most disastrous known lahar occurred in 1985 at Nevado del Ruiz in Colombia and killed more than 23,000 people. Since that disaster, an increasing awareness of lahar hazards has led to efforts to mitigate them. In recent decades, improved land-use decisions, monitoring and communication have improved hazard responses and saved many lives. Lahar hazard maps and development of lahar inundation models have helped planners and people at risk to better understand the nature of the risk owing to lahars.

Book chapter

Need and vision for global medium-resolution Landsat and Sentinel-2 data products

Global changes in climate and land use are threatening natural ecosystems, biodiversity, and the ecosystem services people rely on. This is why it is necessary to track and monitor spatiotemporal change at a level of detail that can inform science, management, and policy development. The current constellation of multiple Landsat and Sentinel-2 satellites collecting imagery at predominantly ≤ "> ≤ 30-m spatial resolution affords an opportunity for the generation of global medium- resolution products every few days. Our goal is to both identify the information needs and provide direction towards the generation of a suite of global, high-level, systematically-generated, medium-resolution products designed for both management and science. Our vision builds on the success of the NASA MODIS/VIIRS product suite, while recognizing the unique strengths of medium-resolution satellite data given their higher spatial resolution and longer time series. We propose a suite of 13 essential products that enable the characterization of the current state and changes in the biosphere, cryosphere, and hydrosphere, and would fill information needs identified by the Committee on Earth Observation Satellites for the Global Climate Observing System and the Global Terrestrial Observing System, by the National Research Council of the US National Academies in the decadal survey, and by others. These products are: land cover, land cover change, burned area, forest loss, vegetation indices, phenology, dynamic habitat indices, albedo, land surface temperature, snow cover, ice extent, surface water extent, and evapotranspiration. Furthermore, we provide a list of desirable products poised for addition to the essential products (e.g., crop type, emissivity, and ice sheet velocity). Lastly, we suggest aspirational products requiring further algorithm development (e.g., forest structure and crop yield). For the identified essential products, algorithms are in place, making it feasible to begin generating products systematically. These products should be accompanied by quality and accuracy assessments undertaken following consensus protocols. Five decades after the first Landsat satellite, and two decades after the MODIS products were first produced, it is time now for readily available, standardized, and consistent high-level products built upon medium-resolution imagery, thereby fulfilling the promise and the vision that inspired the Landsat program since its inception.

Remote Sensing of Environment

The macroecology of sustainability

The discipline of sustainability science has emerged in response to concerns of natural and social scientists, policymakers, and lay people about whether the Earth can continue to support human population growth and economic prosperity. Yet, sustainability science has developed largely independently from and with little reference to key ecological principles that govern life on Earth. A macroecological perspective highlights three principles that should be integral to sustainability science: 1) physical conservation laws govern the flows of energy and materials between human systems and the environment, 2) smaller systems are connected by these flows to larger systems in which they are embedded, and 3) global constraints ultimately limit flows at smaller scales. Over the past few decades, decreasing per capita rates of consumption of petroleum, phosphate, agricultural land, fresh water, fish, and wood indicate that the growing human population has surpassed the capacity of the Earth to supply enough of these essential resources to sustain even the current population and level of socioeconomic development.

PLoS Biology

A snapshot of women of the U.S. Geological Survey in STEM and related careers

Introduction The term “STEM” has been used to group together the fields of science, technology, engineering, and mathematics and to describe education and professions related to these fields. The professional fields connected to STEM education are thought of as engineering, medicine, and computer technology. Yet these professional fields are merely the tip of the iceberg. Numerous opportunities in these fields encompass environmental research. The possibilities range from predicting the next earthquake to saving polar bears from extinction to developing a vaccine for salmon measles. The science of natural systems is complex and often requires people from a variety of fields of expertise to make headway with a solution. To that end, the U.S. Geological Survey (USGS) has long recognized the need for a diversity of STEM expertise to address the Nation’s environmental research needs and the vision to facilitate integration of these fields. We are team builders! In this book, we point out the many facets of research carried out by USGS STEM scientists in an effort to show career options and pathways not typically pursued. The women portrayed were selected by USGS associate and regional directors as representative of particular fields and to inspire future generations.

Circular

Impacts of climate change on ecosystem services

Key Findings By 2050, climate change will triple the fraction of counties in the U.S. that are at high or extremely high risk of outstripping their water supplies (from 10 percent to 32 percent). The most at risk areas in the U.S. are the West, Southwest and Great Plains regions. Regulation of drinking water quality will be strained as high rainfall and river discharge conditions may lead to higher levels of nitrogen in rivers and greater risk of waterborne disease outbreaks. Climate change will have uneven effects on timber production across the U.S. Recent increases in tree mortality due to disease and pests, and the intensity of fires and area burned will continue to destroy productive forests. On the other hand, in some regions climate change is expected to boost overall forest productivity due to longer growing seasons. There is a better than 50 percent chance that climate change will overwhelm the ability of natural systems to mitigate the harm to people resulting from extreme weather events (such as heat waves, heavy rains, and drought). Vulnerability of people and property in coastal areas is highly likely to increase dramatically – due to the effects of sea-level rise, storm surge, and the loss of habitats that provide protection from flooding and erosion. The areas at greatest risk to coastal hazards in the U.S. are the Atlantic and Gulf coasts. The human communities most vulnerable to climate-related increases in coastal hazards are the elderly and the poor who are less able to respond quickly before and during hazards and to respond over the long term through relocation. Changes in abundance and ranges of commercially important marine fish are highly likely to result in loss of some local fisheries, and increases in value for others if fishing communities and management practices can adapt. In recreation and tourism, the greatest negative climate impacts will continue to be felt in winter sports and beach recreation (due to coastal erosion). Other forms of recreation are highly likely to increase due to better weather, leading to a redistribution of the industry and its economic impacts, with visitors and tourism dollars shifting away from some communities in favor of others. Supporting, regulating, and provisioning ecosystem services all contribute to food security in the United States, and the fate of the nation’s food production are very likely to depend on the interplay of these services and how the agriculture and fishery sectors respond to climate stresses.

Book chapter

Communicating hazards—A social science review to meet U.S. Geological Survey needs

This report is for U.S. Geological Survey (USGS)—and any other—hazard scientists who want to improve the understanding and use of their scientific information, particularly by non-experts. In order for people to use science, they need to understand it. The highly technical, specialized nature of scientific information makes that difficult, particularly when few scientists are trained to communicate with people outside their fields. These issues are of special importance to the USGS because it has many users who are not scientists and because it develops and applies hazard science to help protect the safety, security, and economic well-being of our Nation. In 2010, the Science Application for Risk Reduction group at the USGS discovered the Center for Research on Environmental Decisions (CRED) guide, “The Psychology of Climate Change Communication.” Ever since, a growing number of USGS staff who need to communicate about hazards have used that guide and have asked CRED for a companion report dedicated to hazard communication to harness knowledge from more than 50 years of social science research. In 2016, the USGS and CRED launched a collaboration to develop that companion report. Ultimately, a CRED hazard communication guide would be a Columbia University publication with a wide focus and would include many hazards that are outside the USGS purview. This report is a first step and concentrates strictly on hazard communication needs at the USGS. To identify those needs and tailor this effort to USGS hazard communication priorities, this collaboration began with telephone interviews and an online survey of USGS staff. This report is the result; it summarizes social science research and experience in the areas of hazard communication that USGS participants deemed most important to include.

Circular

The risk reduction benefits of the Mesoamerican Reef in Mexico

Coastal development and climate change are dramatically increasing the risks of flooding, erosion, and extreme weather events. Coral reefs and other coastal ecosystems act as natural defenses against coastal hazards, but their degradation increases risk to people and property. Environmental degradation, however, has rarely been quantified as a driver of coastal risk. In Quintana Roo, Mexico, a region on the Mexican Caribbean coast with an annual tourism economy of 10 billion USD, coral reefs constitute a natural barrier against flooding from hurricanes. This study spatially quantifies the risk reduction benefits of the Mesoamerican Reef in Quintana Roo for people, buildings, and hotel infrastructure. The risk reduction benefits are substantial. For example, the reefs prevented 43% additional damage during Hurricane Dean in (2007) and provide nowadays hazard risk reduction for 4.3% of the people, 1.9% of the built capital, and 2.4% of the hotel infrastructure, per year. The annual benefits are estimated in 4,600 people, 42 million USD damage prevention for buildings, and 20.8 million USD for hotel infrastructure. The study also compares the risk reduction of coral reefs with (i) the protection offered by dunes and (ii) the increase in coastal risk from sea-level rise (SLR). The risk reduction of dunes is more critical where there are no coral reefs offshore and for small return-periods storms. Sea-level rise, however, will make the more frequent storms more impactful and will drive significant increases in annual expected damages across the region. However, we demonstrate that, in coral reef environments, the contribution of reef degradation to coastal risk is larger than the expected increase in risk from SLR. However, the spatial distribution of the risk reduction benefits from reefs differs for people and infrastructure, and in particular for hotels, which receive the most protection from reefs. Furthermore, many sections present larger benefits than the typical costs of restoration. This valuation makes a compelling case for protecting and maintaining this natural infrastructure for its risk reduction service, but also allows the development of piloting innovative strategies, such as risk finance and insurance strategies, that can align environmental and risk management goals.

Mesoamerican Reef

A primer on water

When you open the faucet you expect water to flow. And you expect it to flow night or day, summer or winter, whether you want to fill a glass or water the lawn. It should be clean and pure, without any odor. You have seen or read about places where the water doesn't have these qualities. You may have lived in a city where you were allowed to water the lawn only during a few hours of certain days. We know a large town where the water turns brown after every big rainstorm. Beginning shortly after World War II, large areas in the Southwestern United States had a 10-year drought, and newspapers published a lot of information about its effects. Some people say that the growing demand for water will cause serious shortages over much of the country in the next 10 to 40 years. But it has always been true that while water wells and springs dry up in some places, floods may be occurring in other places at the same time. Nearly every month news stories are published describing floods somewhere in the country. In fact, every year, on the average, 75,000 persons are forced from their homes by floods. In some years, as in 1951 when the lower Kansas River experienced a great flood, half a million people are affected. To understand the reasons for such recurring distress, it is necessary to know something about rivers and about the flat land or flood plain that borders the river. Interest in water and related problems is growing as our population increases and as the use of water becomes steadily greater. To help meet this heightened interest in general information about water and its use and control is the reason this primer was written. The primer is in two parts. The first part tells about hydrology, or the science that concerns the relation of water to our earth, and the second part describes the development of water supplies and the use of water. The Geological Survey is publishing this primer in nontechnical language in the hope that it will enable the general reader to understand the facts about water as a part of nature, and that by having this understanding the people can solve their water problems. We, as representatives of the Geological Survey, acknowledge with thanks the helpful suggestions made on an early draft by Marion Loizeaux, Maria Lord Converse, Constance Foley, Laura R. Langbein, and Bruce C. Leopold. We are also indebted to various geologists and engineers of the Survey for their discerning critical reviews.

General Interest Publication

Synthesis of natural flows at selected sites in and near the Milk River basin, Montana, 1928-89

Natural monthly streamflows were synthesized for the years 1928-89 at 2 sites in the St. Mary River Basin and 11 sites in the Milk River Basin in north- central Montana. The sites are represented as nodes in a streamflow accounting model being developed by the Bureau of Reclamation for the Milk River Basin. Recorded flows at most sites have been affected by human activities, including reservoir storage and irrigation diversions. The flows at the model nodes were corrected for the effects of these activities to obtain synthesized flows. The synthesized flows at nodes with seasonal and short-term records were extended using a statistical technique. The methods of synthesis varied, depending on upstream activities and information available. Flows at sites in the St. Mary River Basin and at the Milk River at Eastern Crossing of International Boundary pre- viously had been synthesized. The flows at mainstem sites downstream from the Milk River at Eastern Crossing were synthesized by adding synthesized natural runoff from intervening drainage areas to natural flows for Milk River at Eastern Crossing. Natural runoff from intervening drainage areas was estimated by multiplying recorded flows at selected index gaging stations on tributary streams by the ratio of the intervening drainage area to the combined drainage area of the index stations. The recorded flows for Milk River at Western Crossing of International Boundary and for Peoples Creek near Dodson, Montana, were assumed to be natural flows. The synthesized annual flows at the mouth of the Milk River compared favorably with the recorded flows near the mouth when the effects of upstream irrigation were considered.

Water-Resources Investigations Report

The nature of earthquake prediction

Earthquake prediction is inherently statistical. Although some people continue to think of earthquake prediction as the specification of the time, place, and magnitude of a future earthquake, it has been clear for at least two decades that this is an unrealistic and unreasonable definition. The reality is that earthquake prediction starts from long-term forecasts of place and magnitude, with very approximate time constraints, and progresses, at least in principle, to a gradual narrowing of the time window as data and understanding permit. The analogy to catching a rabbit in an overgrown confined field may be appropriate. You do not just start out looking for the rabbit, you instead build a fence dividing the field in two and then decide which half the rabbit is in, thereby gaining one bit of information. You iterate this process until you have located the rabbit “close enough for practical purposes.” This is approximately how earthquake prediction proceeds in the real world, with time and position along a fault comprising the two dimensions of the search. (I assume here that we are considering for the moment only large earthquakes, that is those capable of inflicting serious damage on a regional scale; in California this means events of about M 6.7 and larger.) This more realistic perspective on the problem lays to rest the “red herring” that “earthquake predictions might do more harm than earthquakes.” These imaginary concerns are predicated on the fantasy of a prediction that precisely specifies time, place, and magnitude; in the real world a progression of probabilities that narrows the space-time window in small steps clearly carries no such threat.

Seismological Research Letters

The nature of earthquake prediction

Earthquake prediction is inherently statistical. Although some people continue to think of earthquake prediction as the specification of the time, place, and magnitude of a future earthquake, it has been clear for at least a decade that this is an unrealistic and unreasonable definition. the reality is that earthquake prediction starts from the long-term forecasts of place and magnitude, with very approximate time constraints, and progresses, at least in principle, to a gradual narrowing of the time window as data and understanding permit. Primitive long-term forecasts are clearly possible at this time on a few well-characterized fault systems. Tightly focuses monitoring experiments aimed at short-term prediction are already underway in Parkfield, California, and in the Tokai region in Japan; only time will tell how much progress will be possible.

Earthquakes & Volcanoes (USGS)

Natural Hazards Science at the U.S. Geological Survey

The mission of the USGS in natural hazards is to develop and apply hazard science to help protect the safety, security, and economic well-being of the Nation. The costs and consequences of natural hazards can be enormous, and each year more people and infrastructure are at risk. The USGS conducts hazard research and works closely with stakeholders and cooperators to inform a broad range of planning and response activities at individual, local, State, national, and international levels. It has critical statutory and nonstatutory roles regarding floods, earthquakes, tsunamis, landslides, coastal erosion, volcanic eruptions, wildfires, and magnetic storms. USGS science can help to understand and reduce risks from natural hazards by providing the information that decisionmakers need to determine which risk management activities are worth­while.

Fact Sheet

Using the value of information to improve conservation decision making

Conservation decisions are challenging, not only because they often involve difficult conflicts among outcomes that people value, but because our understanding of the natural world and our effects on it is fraught with uncertainty. Value of Information (VoI) methods provide an approach for understanding and managing uncertainty from the standpoint of the decision maker. These methods are commonly used in other fields (e.g., economics, public health) and are increasingly used in biodiversity conservation. This decision analytical approach can identify the best management alternative to select where the effectiveness of interventions is uncertain, and can help to decide when to act and when to delay action until after further research. We review the use of VoI in the environmental domain, reflect on the need for greater uptake of VoI, particularly for strategic conservation planning, and suggest promising areas for new research. We also suggest common reporting standards as a means of increasing the leverage of this powerful tool. The environmental science, ecology and biodiversity categories of the Web of Knowledge were searched using the terms ‘Value of Information,’ ‘Expected Value of Perfect Information,’ and the abbreviation ‘EVPI.’ Google Scholar was searched with the same terms, and additionally the terms decision and biology, biodiversity conservation, fish, or ecology. We identified 1225 papers from these searches. Included studies were limited to those that show an application of VoI in biodiversity conservation rather than simply describing the method. All examples of use of VOI were summarised regarding the application of VoI, the management objectives, the uncertainties, models used, how the objectives were measured, and the type of VoI. While the use of VoI appears to be on the increase in biodiversity conservation, the reporting of results is highly variable, which can make it difficult to understand the decision context and which uncertainties were considered. Moreover, it was unclear if, and how, the papers informed management and policy interventions, which is why we suggest a range of reporting standards that would aid the use of VoI. The use of VoI in conservation settings is at an early stage. There are opportunities for broader applications, not only for species-focussed management problems, but also for setting local or global research priorities for biodiversity conservation, making funding decisions, or designing or improving protected area networks and management. The long-term benefits of applying VoI methods to biodiversity conservation include a more structured and decision-focused allocation of resources to research.

Biological Reviews

Flooding: A unique year

Floods have been and continue to be one of the most destructive hazards facing the people of the United States. Of all the natural hazards, floods are the most widespread and the most ruinous to life and property. Today, floods are a greater menace to our welfare than ever before because we live in large numbers near water and have developed a complex reliance upon it. From large rivers to country creeks, from mountain rills to the trickles that occasionally dampen otherwise arid wastelands, every stream in the United States is subject to flooding at some time. Floods strike in myriad forms, including sea surges driven by wild winds or tsunamis churned into fury by seismic activity. By far the most frequent, however, standing in a class by themselves, are the inland, freshwater floods that are caused by rain, by melting snow and ice, or by the bursting of structures that man has erected to protect himself and his belongings from angry waters.

Yearbook

Potential hazards from future eruptions of Mount St. Helens Volcano, Washington

Mount St. Helens has been more active and more explosive during the last 4,500 years than any other volcano in the conterminous United States. Eruptions of that period repeatedly formed domes, large volumes of pumice, hot pyroclastic flows, and, during the last 2,500 years, lava flows. Some of this activity resulted in mudflows that extended tens of kilometers down the floors of valleys that head at the volcano. This report describes the nature of the phenomena and their threat to people and property; the accompanying maps show areas likely to be affected by future eruptions of Mount St. Helens. Explosive eruptions that produce large volumes of pumice affect large areas because winds can carry the lightweight material hundreds of kilometers from the volcano. Because of prevailing winds, the 180-degree sector east of the volcano will be affected most often and most severely by future eruptions of this kind. However, the pumice from any one eruption will fall in only a small part of that sector. Pyroclastic flows and mudflows also can affect areas far from the volcano, but the areas they affect are smaller because they follow valleys. Mudflows and possibly pyroclastic flows moving rapidly down Swift and Pine Creeks could displace water in Swift Reservoir, which could cause disastrous floods farther downvalley.

Bulletin

Oregon and Landsat

Oregon’s landscape is as complex and diverse as it is beautiful. Mountain peaks in the Cascade Range soar higher than 10,000 feet. Crater Lake sinks to a depth of 1,943 feet, making it the deepest lake in the United States. Oregon’s lands feature forests, farm fields, grasslands, ocean coastline, rivers, a semidesert, and mountain ranges that stretch across the State. A wide range of birds, animals, and fish—including 16 federally endangered species—share this space with more than 4 million people. With Oregon’s economy tied to these natural resources, industries like agriculture, timber, and fishing interlace with the well-being of wildlife and residents. Landsat data and imagery are one of many U.S. Geological Survey tools used by State resource managers and scientists to help achieve a natural balance and provide information about forests, habitats, and much more to Oregon decision makers. This will become even more important as research indicates climate change will make extreme weather more likely, leading to the likely increase in droughts, infestation, wildfires, and other natural hazards.

Oregon

An assessment of volcanic threat and monitoring capabilities in the United States: Framework for a National Volcano Early Warning System

Executive Summary NVEWS – a National Volcano Early Warning System – is being formulated by the Consortium of U.S. Volcano Observatories (CUSVO) to establish a proactive, fully integrated, national-scale monitoring effort that ensures the most threatening volcanoes in the United States are properly monitored in advance of the onset of unrest and at levels commensurate with the threats posed. Volcanic threat is the combination of hazards (the destructive natural phenomena produced by a volcano) and exposure (people and property at risk from the hazards). The United States has abundant volcanoes, and over the past 25 years the Nation has experienced a diverse range of the destructive phenomena that volcanoes can produce. Hazardous volcanic activity will continue to occur, and – because of increasing population, increasing development, and expanding national and international air traffic over volcanic regions – the exposure of human life and enterprise to volcano hazards is increasing. Fortunately, volcanoes exhibit precursory unrest that if detected and analyzed in time allows eruptions to be anticipated and communities at risk to be forewarned with reliable information in sufficient time to implement response plans and mitigation measures. In the 25 years since the cataclysmic eruption of Mount St. Helens, scientific and technological advances in volcanology have been used to develop and test models of volcanic behavior and to make reliable forecasts of expected activity a reality. Until now, these technologies and methods have been applied on an ad hoc basis to volcanoes showing signs of activity. However, waiting to deploy a robust, modern monitoring effort until a hazardous volcano awakens and an unrest crisis begins is socially and scientifically unsatisfactory because it forces scientists, civil authorities, citizens, and businesses into “playing catch up” with the volcano, trying to get instruments and civil-defense measures in place before the unrest escalates and the situation worsens. Inevitably, this manner of response results in our missing crucial early stages of the volcanic unrest and hampers our ability to accurately forecast events. Restless volcanoes do not always progress to eruption; nevertheless, monitoring is necessary in such cases to minimize either over-reacting, which costs money, or under-reacting, which may cost lives. Volcano monitoring in the U.S. is conducted by five volcano observatories, supported primarily by the USGS Volcano Hazards Program. Under the Stafford Act, the USGS is responsible for issuing timely warnings of potential volcanic disasters to the affected populace and civil authorities. To make maximum use of the Nation’s scientific resources, the USGS operates the observatories with the help of universities and other governmental agencies, through formal partnerships. At present, about half of the most threatening U.S. volcanoes are monitored at a basic level with real-time sensors (primarily seismic arrays), and a few are well monitored with a suite of modern instrument types and methods. However, monitoring capabilities at many hazardous volcanoes are known to be sparse or antiquated, and some hazardous volcanoes have no ground-based monitoring whatsoever.

Marianas Islands